Power conversion device

Abstract

A power conversion device according to the present invention comprises: a power module that performs power conversion; a capacitor module that is disposed closer to one side in a first direction than the power module and is electrically connected to the power module; and a housing that accommodates the power module and the capacitor module. The capacitor module has a plurality of capacitor substrates on which capacitors are mounted and which have plate surfaces facing the first direction. Each of the plurality of capacitor substrates is disposed so as to be aligned in the first direction.

Description

Power conversion device

[0001] The present invention relates to a power conversion device. This application claims priority based on Japanese Patent Application No. 2024-189684 filed in Japan on October 29, 2024, and incorporates its content herein by reference.

[0002] There is known a power conversion device in which a power module unit having a plurality of power semiconductor modules and a capacitor unit having a plurality of capacitor elements and electrically connected to the power module unit are each disposed inside a case, and the power module unit is disposed parallel to the capacitor unit (for example, Patent Document 1).

[0003] Japanese Unexamined Patent Application Publication No. 2013-031330

[0004] In the above power conversion device, when a plurality of capacitors are mounted on a capacitor substrate, if the capacitor substrate is disposed in a posture in which the direction of the plate surface is orthogonal to the direction in which the power module unit and the capacitor unit are arranged side by side, the case tends to be enlarged in the direction in which the power module unit and the capacitor unit are arranged side by side. Therefore, it has been difficult to miniaturize the power conversion device.

[0005] One object of one aspect of the present invention is to provide a power conversion device capable of achieving miniaturization in the direction in which a power module and a capacitor module are arranged side by side.

[0006] One aspect of the power conversion device of the present invention includes a power module that performs power conversion, a capacitor module disposed on one side in a first direction relative to the power module and electrically connected to the power module, and a housing that houses each of the power module and the capacitor module. The capacitor module has a plurality of capacitor substrates on which capacitors are mounted and the plate surfaces face the first direction. Each of the plurality of capacitor substrates is arranged side by side along the first direction.

[0007] According to one aspect of the present invention, in a power conversion device, miniaturization can be achieved in the direction in which the power module and the capacitor module are arranged side by side.

[0008] Figure 1 is a first perspective view showing the power converter of the embodiment. Figure 2 is a cross-sectional view showing the power converter of the embodiment. Figure 3 is a first cross-sectional view showing the capacitor module of the embodiment. Figure 4 is a second perspective view showing the power converter of the embodiment. Figure 5 is a perspective view showing the capacitor module of the embodiment. Figure 6 is a first perspective view showing a part of the power converter of the embodiment. Figure 7 is a second perspective view showing a part of the power converter of the embodiment. Figure 8 is a third perspective view showing a part of the power converter of the embodiment. Figure 9 is a second cross-sectional view showing the capacitor module of the embodiment.

[0009] The following description of a power conversion device according to an embodiment of the present invention will be made with reference to the drawings. Note that the scope of the present invention is not limited to the following embodiments, and modifications can be made as appropriate within the scope of the technical concept of the present invention. Furthermore, in the following drawings, the scale and number of components may differ from the actual structure in order to make the components easier to understand.

[0010] In the following description, the first direction D1 will be shown in each figure as appropriate. In this embodiment, the first direction D1 is the left-right direction of the power converter. The first direction D1 is the direction in which the power module and the capacitor module are arranged side by side. In the following description, the side in which the arrow of the first direction D1 points (+D1 side) will be referred to as "one side of the first direction D1" or "left side". The side opposite to the side in which the arrow of the first direction D1 points (-D1 side) will be referred to as "the other side of the first direction D1" or "right side".

[0011] In the following description, the second direction D2 is shown in each figure as appropriate. The second direction D2 is the vertical direction of the power converter. The second direction D2 is the direction that intersects with the first direction D1. In this embodiment, the second direction D2 is perpendicular to the first direction D1. The second direction D2 does not have to be perpendicular to the first direction D1. In the following description, the side to which the arrow of the second direction D2 points (+D2 side) will be referred to as "one side of the second direction D2" or "down side". The side opposite to the side to which the arrow of the second direction D2 points (-D2 side) will be referred to as "the other side of the second direction D2" or "up side".

[0012] In the following description, the third direction D3 is shown in each figure as appropriate. The third direction D3 is the front-to-back direction of the power converter. The third direction D3 is the direction that intersects both the first direction D1 and the second direction D2. In this embodiment, the third direction D3 is the direction that is perpendicular to both the first direction D1 and the second direction D2. The third direction D3 does not have to be perpendicular to at least one of the first direction D1 and the second direction D2. 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".

[0013] Note that the terms left, right, bottom, top, front, and rear are merely names used to describe the relative positions of each part, and the actual arrangement may differ from those indicated by these names.

[0014] Figure 1 is a perspective view showing the power converter 10 of this embodiment. The power converter 10 of this embodiment is a control device that generates a current to be supplied to a motor (not shown) and controls the operation of the motor. In this embodiment, the power converter 10 and the motor (not shown) are each mounted on a vehicle such as a hybrid electric vehicle (HEV), a plug-in hybrid vehicle (PHV), or an electric vehicle (EV) to drive the vehicle. As shown in Figure 2, the power converter 10 comprises a housing 11, a capacitor module 20, a fixing member 35, a power module 40, a bus bar 50, an output bus bar 61, a current sensor 63, and a control board 80.

[0015] The housing 11 is box-shaped and houses the capacitor module 20, the fixing member 35, the power module 40, the busbar 50, a portion of the output busbar 61, the current sensor 63, and the control board 80. In this embodiment, the housing 11 is made of aluminum. The housing 11 may be made of other metal materials such as stainless steel, or of resin. As shown in Figure 1, the housing 11 has a housing 12 and a lid member 13.

[0016] As shown in Figure 2, the housing 12 is a roughly rectangular tube extending in the second direction D2. The housing 12 may also be a polygonal tube, such as a pentagonal tube, or a cylindrical shape, extending in the second direction D2. The housing 12 is open on the top side. Inside the housing 12 are the various parts that constitute the power conversion device 10, such as the capacitor module 20, the fixing member 35, and the power module 40. The housing 12 has a peripheral wall portion 12a and a bottom wall portion 12d.

[0017] The peripheral wall portion 12a is a roughly rectangular tube shape extending in the second direction D2. The peripheral wall portion 12a surrounds the various parts that constitute the power conversion device 10, such as the capacitor module 20, the fixing member 35, and the power module 40. As shown in Figure 1, when viewed from the second direction D2, the peripheral wall portion 12a is a roughly rectangular annular shape with its long side extending in the first direction D1. As shown in Figure 2, the peripheral wall portion 12a has an opening 12b that opens upward. As shown in Figure 1, two cables 70 are attached to the left side (+D1 side) portion of the peripheral wall portion 12a. Each cable 70 is electrically connected to an external power source (not shown). The external power source is, for example, a battery in a vehicle. A first current C1 is supplied to the power conversion device 10 from the external power source (not shown) via each cable 70.

[0018] As shown in Figure 2, the bottom wall portion 12d is plate-shaped and extends in a direction perpendicular to the second direction D2. The outer edge of the bottom wall portion 12d is connected to the lower end of the peripheral wall portion 12a. The bottom wall portion 12d is provided with a bottom wall hole 12e. As shown in Figure 3, the bottom wall portion 12d is provided with a hole portion 12f.

[0019] The bottom wall hole 12e is a hole that penetrates the bottom wall portion 12d in the second direction D2. The bottom wall hole 12e is provided on the right side (-D1 side) of the bottom wall portion 12d. As shown in Figure 3, the hole portion 12f is a female screw hole that is recessed downward from the upper side surface of the bottom wall portion 12d. Although not shown, in this embodiment, the bottom wall portion 12d is provided with two holes 12f. Each hole portion 12f is provided on the left side (+D1 side) of the bottom wall portion 12d. Although not shown, each hole portion 12f is provided spaced apart from each other along the third direction D3.

[0020] As shown in Figure 1, the lid member 13 is plate-shaped and extends in a direction perpendicular to the second direction D2. Viewed from the second direction D2, the lid member 13 is approximately rectangular in shape. As shown in Figure 2, the lid member 13 is fixed to the upper end of the housing 12. In this way, the lid member 13 closes the opening 12b from above.

[0021] As shown in Figure 5, the fixing member 35 is a substantially rectangular parallelepiped extending in the third direction D3. As shown in Figure 2, the fixing member 35 is located at the lower end and left side (+D1 side) of the inside of the housing 12. In this embodiment, the fixing member 35 is made of resin. The fixing member 35 is insulating. As shown in Figure 3, the fixing member 35 is provided with a second hole 35a and a fixing hole 35c.

[0022] The second hole 35a is a hole that penetrates the fixing member 35 in the second direction D2. As shown in Figure 5, the fixing member 35 is provided with two second holes 35a. Each second hole 35a is spaced apart from each other along the third direction D3. Although not shown, when viewed from the second direction D2, each second hole 35a overlaps with different holes 12f of the bottom wall 12d. As shown in Figure 3, bolts 92 are passed through each second hole 35a in the second direction D2. Each bolt 92 is tightened into different holes 12f. In this way, the fixing member 35 is fixed to the housing 11. Note that a member (not shown) may be placed between the fixing member 35 and the housing 11, and the fixing member 35 may be indirectly fixed to the housing 11 via such member.

[0023] The fixing hole portion 35c is a female screw hole formed on the inner circumferential surface, recessed on one side in the first direction D1, from the right side (-D1 side) of the fixing member 35 to the left side (+D1 side). Although not shown in the figures, in this embodiment, four fixing hole portions 35c are provided. Each fixing hole portion 35c is provided spaced apart from one another along the third direction D3.

[0024] As shown in Figure 6, the capacitor module 20 is located in the left (+D1) portion of the inside of the housing 12. The capacitor module 20 is located to the left of the power module 40, i.e., on one side in the first direction D1. The capacitor module 20 is electrically connected to the power module 40 via a busbar 50. The capacitor module 20 smooths the first current C1 supplied from an external power supply (not shown) and supplies it to the power module 40. As shown in Figure 3, the capacitor module 20 has a capacitor board 21, a capacitor 30, and a connecting member 33.

[0025] As shown in Figure 6, the capacitor substrate 21 is a plate shape that extends in a direction perpendicular to the first direction D1. The plate surface of the capacitor substrate 21 faces the first direction D1. Viewed from the first direction D1, the capacitor substrate 21 is substantially rectangular in shape, with its longer side extending in the third direction D3. As shown in Figure 3, a capacitor 30 is mounted on the left side (+D1 side) of the capacitor substrate 21. In this embodiment, the capacitor module 20 has a plurality of capacitor substrates 21. Each of the plurality of capacitor substrates 21 is arranged in a line with spacing between them along the first direction D1. In this embodiment, the capacitor module 20 has three capacitor substrates 21. The number of capacitor substrates 21 in the capacitor module 20 may be two or four or more. Each capacitor substrate 21 has a fixed terminal portion 21b and a connecting terminal portion 21d. The plurality of capacitor substrates 21 include a first capacitor substrate 22 and a second capacitor substrate 26.

[0026] The first capacitor board 22 is the capacitor board 21 that is positioned furthest to the right (+D1 side) among the plurality of capacitor boards 21. The first capacitor board 22 has a base material portion 23, a first positive electrode busbar 24, and a first negative electrode busbar 25.

[0027] The base material 23 is plate-shaped and extends in a direction perpendicular to the first direction D1. Parts of the first positive electrode busbar 24 and parts of the first negative electrode busbar 25 are arranged inside the base material 23. Thus, the base material 23 holds the first positive electrode busbar 24 and the first negative electrode busbar 25, respectively. The base material 23 is insulating. The material constituting the base material 23 is a resin material such as polytetrafluoroethylene (PTFE) and polyimide (PI).

[0028] The first positive electrode busbar 24 is plate-shaped and extends in a direction perpendicular to the first direction D1. The material used to construct the first positive electrode busbar 24 can be a metallic material such as copper or silver. The first positive electrode busbar 24 is electrically conductive. The first positive electrode busbar 24 has a positive electrode body portion 24a, a positive electrode fixed terminal portion 24b, and a first junction terminal portion 24d. As shown in Figure 5, the first positive electrode busbar 24 has a positive electrode input terminal 24e.

[0029] As shown in Figure 3, the positive electrode body portion 24a is plate-shaped and extends in a direction perpendicular to the first direction D1. The positive electrode body portion 24a is located inside the base material portion 23. The positive electrode body portion 24a is provided with a plurality of through holes 24g. Each through hole 24g is a hole that penetrates the positive electrode body portion 24a in the first direction D1. Although not shown in the figure, each through hole 24g extends in the third direction D3. In this embodiment, the positive electrode body portion 24a is provided with three through holes 24g. Each through hole 24g is provided spaced apart from each other along the second direction D2.

[0030] The positive electrode fixed terminal portion 24b is plate-shaped and protrudes downward from the positive electrode main body portion 24a. The positive electrode fixed terminal portion 24b is electrically connected to the positive electrode main body portion 24a. The positive electrode fixed terminal portion 24b protrudes downward from the base material portion 23, that is, to one side of the second direction D2 (+D2 side). The plate surface of the positive electrode fixed terminal portion 24b faces the first direction D1. As shown in Figure 5, in this embodiment, the two positive electrode fixed terminal portions 24b of the first positive electrode busbar 24 are spaced apart from each other along the third direction D3. As shown in Figure 3, the positive electrode fixed terminal portion 24b is provided with a hole portion 24c. The hole portion 24c is a hole that penetrates the positive electrode fixed terminal portion 24b in the first direction D1. Although not shown, the hole portion 24c is approximately circular in shape when viewed from the first direction D1.

[0031] The first bonding terminal portion 24d is plate-shaped and protrudes upward from the positive electrode body portion 24a. The first bonding terminal portion 24d is electrically connected to the positive electrode body portion 24a. The first bonding terminal portion 24d protrudes upward from the base material portion 23. The plate surface of the first bonding terminal portion 24d faces the first direction D1. As shown in Figure 7, in this embodiment, the two first bonding terminal portions 24d of the first positive electrode busbar 24 are arranged spaced apart from each other along the third direction D3.

[0032] The positive electrode input terminal 24e shown in Figure 5 is plate-shaped and protrudes forward (towards +D3) from the positive electrode main body 24a. The positive electrode input terminal 24e is electrically connected to the positive electrode main body 24a. The positive electrode input terminal 24e protrudes forward from the base material 23. In other words, the positive electrode input terminal 24e protrudes in a direction perpendicular to the first direction D1. The positive electrode input terminal 24e may also protrude in the second direction D2. The plate surface of the positive electrode input terminal 24e faces the first direction D1. As shown in Figure 8, the positive electrode input terminal 24e is fixed to the conductive first conductive part 94a by a bolt 93. A positive electrode terminal 71a, electrically connected to one of the cables 70 (see Figure 1), is fixed to the first conductive part 94a. As a result, the positive input terminal 24e is electrically connected to an external power supply (not shown) via the first conductive part 94a, the positive terminal 71a, and one of the cables 70. This electrically connects the external power supply to the first positive busbar 24.

[0033] As shown in Figure 3, the first negative electrode busbar 25 is plate-shaped and extends in a direction perpendicular to the first direction D1. The material used to construct the first negative electrode busbar 25 can be a metallic material such as copper or silver. The first negative electrode busbar 25 is electrically conductive. The first negative electrode busbar 25 is positioned to the right (-D1 side) of the first positive electrode busbar 24. The first negative electrode busbar 25 is spaced apart from the first positive electrode busbar 24 in the first direction D1. This insulates the first negative electrode busbar 25 from the first positive electrode busbar 24. The first negative electrode busbar 25 has a negative electrode body portion 25a, a negative electrode fixing terminal portion 25b, and a second connecting terminal portion 25d. As shown in Figure 5, the first negative electrode busbar 25 has a negative electrode input terminal 25e.

[0034] As shown in Figure 3, the negative electrode body portion 25a is plate-shaped and extends in a direction perpendicular to the first direction D1. The negative electrode body portion 25a is located inside the base material portion 23.

[0035] The negative electrode fixed terminal portion 25b is plate-shaped and protrudes downward from the negative electrode main body portion 25a. The negative electrode fixed terminal portion 25b is electrically connected to the negative electrode main body portion 25a. The negative electrode fixed terminal portion 25b protrudes downward from the base material portion 23, that is, to one side of the second direction D2 (+D2 side). The plate surface of the negative electrode fixed terminal portion 25b faces the first direction D1. As shown in Figure 5, in this embodiment, the first negative electrode busbar 25 has two negative electrode fixed terminal portions 25b. Each negative electrode fixed terminal portion 25b is spaced apart from each other along the third direction D3. Viewed from the first direction D1, each negative electrode fixed terminal portion 25b is positioned offset from the positive electrode fixed terminal portion 24b in the third direction D3. The negative electrode fixed terminal portion 25b is provided with a hole 25c. The hole 25c is a hole that penetrates the negative electrode fixing terminal portion 25b in the first direction D1. Although not shown in the illustration, the hole 25c is approximately circular in shape when viewed from the first direction D1.

[0036] As shown in Figure 3, the second junction terminal portion 25d is plate-shaped and protrudes upward from the negative electrode body portion 25a. The second junction terminal portion 25d is electrically connected to the negative electrode body portion 25a. The second junction terminal portion 25d protrudes upward from the base material portion 23. The plate surface of the second junction terminal portion 25d faces the first direction D1. As shown in Figure 7, in this embodiment, the first negative electrode busbar 25 has two second junction terminal portions 25d. Each second junction terminal portion 25d is spaced apart from each other along the third direction D3. Viewed from the first direction D1, each second junction terminal portion 25d is positioned offset from the first junction terminal portion 24d in the third direction D3.

[0037] The negative electrode input terminal 25e shown in Figure 5 is plate-shaped and protrudes forward (towards +D3) from the negative electrode main body 25a. The negative electrode input terminal 25e is electrically connected to the negative electrode main body 25a. The negative electrode input terminal 25e protrudes forward from the base material 23. In other words, the negative electrode input terminal 25e protrudes in a direction perpendicular to the first direction D1. The negative electrode input terminal 25e is positioned below the positive electrode input terminal 24e. The plate surface of the negative electrode input terminal 25e faces the first direction D1. As shown in Figure 8, the negative electrode input terminal 25e is fixed to the conductive second conductive part 94b by a bolt 93. A negative electrode terminal 71c, which is electrically connected to the other cable 70 (see Figure 1), is also fixed to the second conductive part 94b. As a result, the negative input terminal 25e is electrically connected to an external power supply (not shown) via the second conductive part 94b, the negative terminal 71c, and the other cable 70. This electrically connects the external power supply to the first negative busbar 25. As described above, the external power supply is electrically connected to the first positive busbar 24. As a result, the first current C1 is supplied from the external power supply to the first capacitor board 22.

[0038] As shown in Figure 3, the second capacitor board 26 is a capacitor board 21 that is located to the left (-D1 side) of the first capacitor board 22 among a plurality of capacitor boards 21. In this embodiment, the capacitor module 20 has two second capacitor boards 26. Each second capacitor board 26 is spaced apart in the first direction D1. The second capacitor board 26 has a base material portion 23, a second positive electrode busbar 28, and a second negative electrode busbar 29. The configuration of the base material portion 23 of the second capacitor board 26 is the same as the configuration of the base material portion 23 of the first capacitor board 22.

[0039] The second positive busbar 28 is plate-shaped and extends in a direction perpendicular to the first direction D1. The second positive busbar 28 has a positive body portion 24a, a positive fixed terminal portion 24b, and a first connection terminal portion 24d. The configuration of the positive body portion 24a, positive fixed terminal portion 24b, and first connection terminal portion 24d of the second positive busbar 28 is the same as the configuration of the positive body portion 24a, positive fixed terminal portion 24b, and first connection terminal portion 24d of the first positive busbar 24 described above. In this embodiment, the second positive busbar 28 does not have a positive input terminal 24e. The other configurations of the second positive busbar 28 are the same as the other configurations of the first positive busbar 24 described above.

[0040] The second negative electrode busbar 29 is plate-shaped and extends in a direction perpendicular to the first direction D1. The second negative electrode busbar 29 is positioned to the right (-D1 side) of the second positive electrode busbar 28. The second negative electrode busbar 29 is positioned with a gap between it and the second positive electrode busbar 28 in the first direction D1. As a result, the second negative electrode busbar 29 and the second positive electrode busbar 28 are insulated from each other. The second negative electrode busbar 29 has a negative electrode body portion 25a, a negative electrode fixed terminal portion 25b, and a second connection terminal portion 25d. The configuration of the negative electrode body portion 25a, negative electrode fixed terminal portion 25b, and second connection terminal portion 25d of the second negative electrode busbar 29 is the same as the configuration of the negative electrode body portion 25a, negative electrode fixed terminal portion 25b, and second connection terminal portion 25d of the first negative electrode busbar 25 described above. In this embodiment, the second negative busbar 29 does not have a negative input terminal 25e. The other configurations of the second negative busbar 29 are the same as those of the first negative busbar 25 described above.

[0041] As shown in Figure 2, each of the multiple capacitor substrates 21 has multiple fixed terminal portions 21b and multiple junction terminal portions 21d. In this embodiment, the multiple fixed terminal portions 21b include multiple positive electrode fixed terminal portions 24b and multiple negative electrode fixed terminal portions 25b. As described above, each of the positive electrode fixed terminal portions 24b and each of the negative electrode fixed terminal portions 25b protrudes downward, that is, to one side of the second direction D2 (+D2 side). Thus, each of the multiple capacitor substrates 21 has a fixed terminal portion 21b that protrudes downward. As described above, the positive electrode fixed terminal portion 24b is provided with a hole portion 24c that penetrates the positive electrode fixed terminal portion 24b in the first direction D1. Similarly, the negative electrode fixed terminal portion 25b is provided with a hole portion 25c that penetrates the negative electrode fixed terminal portion 25b in the first direction D1. As a result, the fixed terminal portion 21b is provided with holes 24c and 25c that penetrate the fixed terminal portion 21b in the first direction D1.

[0042] In the present embodiment, the plurality of bonding terminal portions 21d include a plurality of first bonding terminal portions 24d and a plurality of second bonding terminal portions 25d. As described above, each of the first bonding terminal portions 24d and each of the second bonding terminal portions 25d protrudes upward, that is, on the other side (-D2 side) in the second direction D2. As a result, each of the plurality of capacitor substrates 21 has a bonding terminal portion 21d that protrudes upward.

[0043] As shown in FIG. 5, the first capacitor substrate 22 has a plurality of input terminals 21e. In the present embodiment, the plurality of input terminals 21e include a positive input terminal 24e and a negative input terminal 25e. As described above, each of the positive input terminal 24e and the negative input terminal 25e protrudes in the third direction D3, that is, in a direction orthogonal to the first direction D1. Therefore, according to the present embodiment, among the plurality of capacitor substrates 21, the capacitor substrate 21 disposed on the rightmost side, that is, on the other side (-D1 side) in the first direction D1, has an input terminal 21e that protrudes in a direction orthogonal to the first direction D1. That is, as shown in FIG. 8, the capacitor substrate 21 disposed closest to the power module 40 has an input terminal 21e. Therefore, in the first direction D1, the distance between each input terminal 21e and the power module 40 can be reduced. Therefore, in the first direction D1, that is, in the direction in which the power module 40 and the capacitor module 20 are arranged side by side, the power conversion device 10 can be suitably downsized.

[0044] As shown in FIG. 5, the connecting member 33 is cylindrical and extends in the first direction D1. As shown in FIG. 3, the connecting member 33 is provided with a through hole 33a. The through hole 33a is a hole that penetrates the connecting member 33 in the first direction D1. As a result, the connecting member 33 is open on both sides in the first direction D1. Although not shown, when viewed from the first direction D1, the through hole 33a is substantially circular. In the present embodiment, as the material constituting the connecting member 33, a metal material such as copper and silver can be used. The connecting member 33 has conductivity. As shown in FIG. 5, in the present embodiment, the capacitor module 20 has eight connecting members 33.

[0045] Each connecting member 33 is positioned between adjacent fixed terminal portions 21b in the first direction D1. As shown in Figure 3, a fastening member 91 is passed through the through hole 33a and the hole portion 24c in the first direction D1. In this embodiment, the fastening member 91 is a bolt. The fastening member 91 is tightened into the fixed hole portion 35c. As a result, as shown in Figure 5, each of the four connecting members 33 and each of the positive electrode fixed terminal portions 24b is fixed to the fixed member 35. Although not shown, a fastening member 91 is passed through the through hole 33a and the hole portion 25c in the first direction D1. The fastening member 91 is tightened into the fixed hole portion 35c. As a result, each of the four connecting members 33 and each of the negative electrode fixed terminal portions 25b is fixed to the fixed member 35. Therefore, each of the connecting member 33 and the fixed terminal portion 21b is fixed to the fixed member 35 by fastening members 91 that pass through the through hole 33a and the hole portions 24b and 25b respectively and are tightened into the fixed hole portion 35c. In this way, each capacitor board 21 is fixed to the fixed member 35.

[0046] Each connecting member 33 is in contact with the fixed terminal portion 21b, which is arranged adjacent to each other in the first direction D1, in the first direction D1. As described above, the connecting members 33 are conductive. As a result, as shown in Figure 3, the first positive busbar 24 and the two second positive busbars 28 are electrically connected to each other via the connecting members 33. Although not shown in the figure, the first negative busbar 25 and the two second negative busbars 29 are also electrically connected via the connecting members 33. Therefore, the connecting members 33 allow each capacitor board 21 to be electrically connected to each other. As described above, each of the first positive busbar 24 and the first negative busbar 25 is electrically connected to an external power supply (not shown). Therefore, the first current C1 is supplied from the external power supply to each capacitor board 21 via the connecting members 33.

[0047] As shown in FIG. 9, for example, when a plurality of capacitor substrates 21 include one first capacitor substrate 22 and one second capacitor substrate 26, the capacitor module 20 has four connection members 33. In this case, each of the two connection members 33 and each positive electrode fixing terminal portion 24b are fixed to the fixing member 35 by a fastening member 91. Although not shown, each of the two connection members 33 and each negative electrode fixing terminal portion 25b are fixed to the fixing member 35 by a fastening member 91.

[0048] Also, although not shown, when the plurality of capacitor substrates 21 include one first capacitor substrate 22 and three second capacitor substrates 26, the capacitor module 20 has twelve connection members 33. In this case, although not shown, each of the six connection members 33 and each positive electrode fixing terminal portion 24b are fixed to the fixing member 35 by a fastening member 91. Although not shown, each of the six connection members 33 and each negative electrode fixing terminal portion 25b are fixed to the fixing member 35 by a fastening member 91. Thus, in the present embodiment, the number of capacitor substrates 21 included in the capacitor module 20 can be easily changed. Also, as shown in FIGS. 3 and 9, regardless of the number of capacitor substrates 21 included in the capacitor module 20, the dimension of the capacitor module 20 in the second direction D2 is a constant dimension. Therefore, in the present embodiment, while suppressing the increase in size of the power conversion device 10 in the second direction D2, the number of capacitor substrates 21 can be changed. Thereby, while suppressing the increase in size of the power conversion device 10 in the second direction D2, the capacitance of the capacitor module 20 can be changed according to the power output by the power conversion device 10 or the like.

[0049] The capacitor 30 shown in Figure 2 smooths the first current C1 supplied to each capacitor board 21 from an external power source (not shown). In this embodiment, the capacitor 30 is a multilayer ceramic capacitor. Therefore, compared to the case where the capacitor 30 is a film capacitor, it is possible to achieve both a large capacitance and a small size for the capacitor 30. As a result, the capacitor module 20 can be made smaller, and thus the power conversion device 10 can be made smaller.

[0050] In this embodiment, multiple capacitors 30 are mounted on each of the left-facing (+D1 side) surfaces of the multiple capacitor boards 21. As shown in Figure 6, in this embodiment, 18 capacitors 30 are mounted on each capacitor board 21. The number of capacitors 30 mounted on each capacitor board 21 may be 17 or less, or 19 or more. On each capacitor board 21, the multiple capacitors 30 are arranged in a line along the second direction D2 and the third direction D3, respectively. As shown in Figures 2 and 6, in this embodiment, the multiple capacitors 30 are arranged in a line of 6 along the second direction D2 and 3 along the third direction D3. Therefore, according to this embodiment, the mounting density of the multiple capacitors 30 can be increased on each capacitor board 21. This makes it possible to increase the capacitance of the capacitor module 20 while miniaturizing the capacitor module 20 in the second direction D2 and the third direction D3.

[0051] Although not shown in the diagram, on each capacitor board 21, the positive terminal of each capacitor 30 is electrically connected to the positive body portion 24a shown in Figure 3. This connects each capacitor 30 to either the first positive busbar 24 or the second positive busbar 28. Although not shown in the diagram, the negative terminal of each capacitor 30 is passed through through holes 24g provided in the first positive busbar 24 or the second positive busbar 28 in the first direction D1, and is electrically connected to the negative body portion 25a. This connects each capacitor 30 to either the first negative busbar 25 or the second negative busbar 29. Thus, each capacitor 30 is electrically connected to an external power supply (not shown).

[0052] According to this embodiment, each of the plurality of capacitor substrates 21 has a fixed terminal portion 21b that protrudes to one side (+D2 side) in the second direction D2, and the capacitor module 20 has a connecting member 33 that contacts each of the adjacent fixed terminal portions 21b arranged in the first direction D1, the connecting member 33 is provided with a through hole 33a that penetrates in the first direction D1, the fixed terminal portions 21b are provided with holes 24c and 25c that penetrate the fixed terminal portion 21b in the first direction D1, the fixing member 35 is provided with a fixing hole portion 35c that is recessed on the left side (+D1 side), i.e., one side in the first direction D1, and has a female thread formed on its inner circumferential surface, and the connecting member 33 and the fixed terminal portions 21b are fixed to the fixing member 35 by fastening members 91 that pass through the through hole 33a and the holes 24c and 25c respectively and are tightened into the fixing hole portion 35c. Therefore, each capacitor board 21 is fixed to the fixing member 35 by a fastening member 91 via a connecting member 33. As a result, as described above, the number of capacitor boards 21 in the capacitor module 20 can be easily changed. This allows the number of capacitor boards 21 to be appropriately changed according to the power output of the power converter 10, and thus the capacitance of the capacitor module 20 can be easily changed. Therefore, even if the power supplied to a motor (not shown) differs for each power converter 10, a current with a desired waveform can be supplied to the motor without significantly changing the configuration of the power converter 10.

[0053] Furthermore, in this embodiment, as described above, the dimension of the capacitor module 20 in the second direction D2 is constant regardless of the number of capacitor boards 21 in the capacitor module 20. Therefore, for example, even when the power output of the power converter 10 is large, the number of capacitor boards 21 can be increased while suppressing an increase in the size of the power converter 10 in the second direction D2. This makes it possible to increase the capacitance of the capacitor module 20 in accordance with the power output of the power converter 10, while suppressing an increase in the size of the power converter 10 in the second direction D2.

[0054] According to this embodiment, the connecting member 33 is conductive. Therefore, as described above, the connecting member 33 can electrically connect each capacitor board 21 to each other. In other words, the connecting member 33 has the function of fixing each capacitor board 21 to each other and the function of electrically connecting each capacitor board 21 to each other. Therefore, compared to a configuration in which the capacitor module 20 has an additional separate member for electrically connecting each capacitor board 21 to each other, it is possible to suppress an increase in the number of components of the capacitor module 20. Therefore, it is possible to suitably suppress an increase in the manufacturing cost and manufacturing man-hours of the power conversion device 10.

[0055] According to this embodiment, the fixing member 35 is made of resin. Therefore, the fixing member 35 has insulating properties. As a result, the first current C1 flowing through the connecting member 33, that is, the current supplied to the capacitor module 20 from an external power source (not shown), can be prevented from flowing into the housing 11 via the fixing member 35. Consequently, the stability of the operation of the power converter 10 can be improved.

[0056] Furthermore, in this embodiment, as described above, since the fixing member 35 is insulating, it is possible to suppress short circuits between the first positive busbar 24 and the second positive busbar 28 and the first negative busbar 25 and the second negative busbar 29 via the fixing member 35. Therefore, the operational stability of the power converter 10 can be more favorably improved.

[0057] As shown in Figure 6, the power module 40 is positioned to the right (+D1 side) of the capacitor module 20. As shown in Figure 2, the power module 40 is positioned adjacent to the capacitor module 20 in the first direction D1. The power module 40 generates a second current C2 of a predetermined waveform from a first current C1 supplied by an external power supply (not shown), and supplies the second current C2 to a motor (not shown). More specifically, the power module 40 is electrically connected to each of the U-phase coil, V-phase coil, and W-phase coil (not shown) of the motor, and supplies phase currents (U-phase current, V-phase current, and W-phase current) to each coil. In this embodiment, the power module 40 converts the first current C1, which is a DC current, into a second current C2, which is an AC current, and supplies it to the motor. As shown in Figure 7, the power module 40 has a power board 40a, a positive electrode supply terminal 41a, and a negative electrode supply terminal 41c. As shown in Figure 6, the power module 40 has an output terminal 42 and a holding part 45.

[0058] The power substrate 40a has switching elements (not shown). Each switching element generates a second current C2 from a first current C1. In this embodiment, the switching elements are power semiconductor elements such as insulated gate bipolar transistors (IGBTs) and metal-oxide-semiconductor field-effect transistors (MOSFETs). The power substrate 40a has a plurality of switching elements. As a result, the power module 40 can generate a second current C2 which is a three-phase alternating current.

[0059] The positive electrode supply terminal 41a shown in Figure 7 protrudes to the left (+D1 side) from the power board 40a. The positive electrode supply terminal 41a is electrically connected to the power board 40a. The positive electrode supply terminal 41a is conductive. The power module 40 has three positive electrode supply terminals 41a. Each positive electrode supply terminal 41a is spaced apart from each other along the third direction D3. Although not shown in the figure, each positive electrode supply terminal 41a is provided with a female screw hole that penetrates the positive electrode supply terminal 41a in the second direction D2.

[0060] The negative electrode supply terminal 41c protrudes to the left (+D1 side) from the power board 40a. The negative electrode supply terminal 41c is electrically connected to the power board 40a. The negative electrode supply terminal 41c is conductive. The power module 40 has three negative electrode supply terminals 41c. Each negative electrode supply terminal 41c is spaced apart from each other along the third direction D3. Viewed from the first direction D1, each negative electrode supply terminal 41c is positioned offset from the positive electrode supply terminal 41a in the third direction D3. Although not shown in the figure, each negative electrode supply terminal 41c is provided with a female screw hole that penetrates the negative electrode supply terminal 41c in the second direction D2.

[0061] As shown in Figure 6, the output terminal 42 protrudes to the right (+D1 side) from the power board 40a. The output terminal 42 is electrically connected to the power board 40a. The output terminal 42 is conductive. The power module 40 has three output terminals 42. Each output terminal 42 is spaced apart from each other along the third direction D3. A second current C2 flows through each output terminal 42. More specifically, phase currents of different phases flow through each output terminal 42. As shown in Figure 2, each output terminal 42 is provided with a hole 42a recessed with a female screw on the lower side of the upper surface of each output terminal 42.

[0062] The holding portion 45 is a substantially rectangular parallelepiped shape extending in the third direction D3. The power board 40a is fixed to the upper-facing surface of the holding portion 45. In this way, the holding portion 45 holds the power board 40a. A refrigerant flow path for which a refrigerant such as water flows may be provided inside the holding portion 45. This allows heat generated in the power board 40a to be transferred to the refrigerant. Furthermore, it is preferable that the refrigerant flow path is connected to a flow path in the vehicle. This allows heat generated in the power board 40a to be discharged to the outside of the power converter 10 via the refrigerant. Therefore, the temperature rise of the power board 40a can be suppressed. The holding portion 45 is provided with a plurality of holding protrusions 45a.

[0063] Each retaining projection 45a is substantially cylindrical in shape and protrudes downward from the retaining portion 45. The lower end of each retaining projection 45a is fixed to the bottom wall portion 12d of the housing 12. In this way, the power module 40 is fixed to the housing 11.

[0064] The busbar 50 shown in Figure 7 electrically connects the power module 40 and the capacitor module 20. In this embodiment, the power converter 10 includes a plurality of busbars 50. The plurality of busbars 50 include a first busbar 51 and a second busbar 53.

[0065] The first busbar 51 electrically connects a plurality of first junction terminals 24d and a plurality of positive electrode supply terminals 41a. As shown in Figure 3, the first busbar 51 has a first main body 51a, a first junction 51c, and a first output 51e.

[0066] As shown in Figure 7, the first main body portion 51a is plate-shaped and extends in the third direction D3. The plate surface of the first main body portion 51a faces the first direction D1. Viewed from the first direction D1, the first main body portion 51a is substantially rectangular in shape, with its longer side extending in the third direction D3. As shown in Figure 3, in the first direction D1, the first main body portion 51a is positioned to the right (-D1 side) of the first capacitor substrate 22. The first main body portion 51a faces the first capacitor substrate 22 with a gap in the first direction D1.

[0067] The first joint portion 51c is plate-shaped and protrudes to the left (+D1 side) from the upper end of the first main body portion 51a. The plate surface of the first joint portion 51c faces the second direction D2. The first joint portion 51c is positioned above the base material portion 23 of each capacitor substrate 21. The first joint portion 51c is provided with two holes 51d. Each hole 51d is a hole that penetrates the first joint portion 51c in the second direction D2. Each hole 51d is provided spaced apart from each other along the first direction D1. As shown in Figure 7, the first busbar 51 has two first joint portions 51c.

[0068] Each first joint portion 51c is arranged at intervals from one another along the third direction D3. As shown in Figure 3, the first joint terminal portion 24d of the first capacitor substrate 22 is passed through the hole 51d on the right side (-D1 side) of each first joint portion 51c in the second direction D2. The first joint terminal portion 24d of the second capacitor substrate 26, which is located on the right side of the two second capacitor substrates 26, is passed through the hole 51d on the left side (+D1 side) of each first joint portion 51c in the second direction D2. The first joint terminal portion 24d of the second capacitor substrate 26, which is located on the left side of the two second capacitor substrates 26, is located to the left of the first joint portion 51c. Each first joint terminal portion 24d is joined to the first joint portion 51c. As a result, as shown in Figure 7, each first joint terminal portion 24d is joined to the first busbar 51. In this embodiment, each first connecting terminal portion 24d is welded to the first connecting portion 51c. Each first connecting terminal portion 24d may also be joined to the first connecting portion 51c by fastening members such as bolts.

[0069] The first output section 51e is plate-shaped and protrudes to the right (-D1 side) from the lower end of the first main body 51a. The plate surface of the first output section 51e faces the second direction D2. A hole is provided in the first output section 51e. The hole is a hole that penetrates the first output section 51e in the second direction D2. In this embodiment, the first busbar 51 has three first output sections 51e. Each first output section 51e is spaced apart from each other along the third direction D3. Each first output section 51e is positioned above each other's different positive electrode supply terminals 41a. When viewed from the second direction D2, the holes provided in each first output section 51e overlap with the female screw holes provided in each of the different positive electrode supply terminals 41a. A bolt (not shown) is passed through the hole in each first output section 51e, and the bolt is tightened into the female screw hole. As a result, each first output unit 51e is connected to a different positive electrode supply terminal 41a.

[0070] The second busbar 53 electrically connects a plurality of second junction terminals 25d and a plurality of negative electrode supply terminals 41c. As shown in Figure 3, the second busbar 53 has a second main body 53a, a second junction 53c, and a second output 53e.

[0071] As shown in Figure 7, the second main body portion 53a is plate-shaped and extends in the third direction D3. The plate surface of the second main body portion 53a faces the first direction D1. Viewed from the first direction D1, the second main body portion 53a is substantially rectangular in shape, with its longer side extending in the third direction D3. As shown in Figure 3, in the first direction D1, the second main body portion 53a is positioned between the first capacitor substrate 22 and the first main body portion 51a. In the first direction D1, a sheet member 56 is positioned between the first main body portion 51a and the second main body portion 53a. That is, a sheet member 56 is positioned between the first busbar 51 and the second busbar 53.

[0072] As shown in Figure 7, the sheet member 56 is sheet-shaped and extends in the third direction D3. The thickness direction of the sheet member 56 is parallel to the first direction D1. Viewed from the first direction D1, the sheet member 56 is substantially rectangular in shape, with its longer side extending in the third direction D3. As shown in Figure 3, in this embodiment, the sheet member 56 is fixed to the left side (+D1 side) of the first main body 51a. The sheet member 56 may also be fixed to the right side (-D1 side) of the second main body 53a. In this embodiment, the sheet member 56 is made of insulating paper. The sheet member 56 may also be made of resin. The sheet member 56 has insulating properties.

[0073] In this embodiment, an insulating sheet member 56 is placed between the first busbar 51 and the second busbar 53. Therefore, the sheet member 56 insulates the first busbar 51 and the second busbar 53 from each other. This allows the first busbar 51 and the second busbar 53 to be placed closer to each other. Consequently, the power converter 10 can be more preferably miniaturized.

[0074] Furthermore, in this embodiment, as described above, in the first direction D1, the sheet member 56 is positioned between the first main body 51a and the second main body 53a. Therefore, the sheet member 56 insulates the first main body 51a and the second main body 53a from each other, allowing the first main body 51a and the second main body 53a to be positioned closer to each other in the first direction D1. Consequently, in the first direction D1, that is, the direction in which the power module 40 and the capacitor module 20 are arranged side by side, the miniaturization of the power converter 10 can be more favorably achieved.

[0075] The second joint portion 53c is plate-shaped and protrudes to the left (+D1 side) from the upper end of the second main body portion 53a. The plate surface of the second joint portion 53c faces the second direction D2. In the second direction D2, the second joint portion 53c is positioned between the base material portion 23 of each capacitor substrate 21 and the first joint portion 51c. As shown in Figure 7, the second joint portion 53c is provided with two holes 53d. Each hole 53d is a hole that penetrates the second joint portion 53c in the second direction D2. Each hole 53d is provided spaced apart from each other along the first direction D1. The second busbar 53 has two second joint portions 53c.

[0076] Each second joint portion 53c is spaced apart from each other along the third direction D3. The second joint terminal portion 25d of the first capacitor board 22 is passed through the hole 53d on the right side (-D1 side) of each second joint portion 53c in the second direction D2. The second joint terminal portion 25d of the second capacitor board 26, which is located on the right side of the two second capacitor boards 26, is passed through the hole 53d on the left side (+D1 side) of each second joint portion 53c in the second direction D2. The second joint terminal portion 25d of the second capacitor board 26, which is located on the left side of the two second capacitor boards 26, is located to the left of the second joint portion 53c. Each second joint terminal portion 25d is joined to the second joint portion 53c. As a result, each second joint terminal portion 25d is joined to the second bus bar 53. As described above, each first joint terminal portion 24d is joined to the first bus bar 51. As a result, the connecting terminal portion 21d is connected to the bus bar 50. Therefore, the capacitor module 20 is electrically connected to the bus bar 50. In this embodiment, each second connecting terminal portion 25d is welded to the second connecting portion 53c. Each second connecting terminal portion 25d may also be connected to the second connecting portion 53c by fastening members such as bolts.

[0077] According to this embodiment, each of the multiple capacitor substrates 21 has a connecting terminal portion 21d that protrudes upward, i.e., to the other side of the second direction D2 (-D2 side), and is joined to the bus bar 50. Therefore, since the connecting terminal portion 21d protrudes upward, the connecting terminal portion 21d and the bus bar 50 can be easily joined from above. Thus, an increase in the manufacturing man-hours of the power conversion device 10 can be effectively suppressed.

[0078] Furthermore, in this embodiment, as shown in Figure 6, the housing 12 has an opening 12b that opens upward. Therefore, the connecting terminal portion 21d can be welded to the busbar 50 from above through the opening 12b. As a result, the connecting terminal portion 21d and the busbar 50 can be joined more easily. Consequently, the increase in manufacturing man-hours for the power conversion device 10 can be more effectively suppressed.

[0079] As described above, in the second direction D2, the second joint portion 53c is positioned between the base material portion 23 of each capacitor substrate 21 and the first joint portion 51c. Therefore, according to this embodiment, as shown in Figure 3, the first joint portion 51c and the second joint portion 53c are positioned offset from each other in the second direction D2. As a result, it is easy to increase the distance between the first joint portion 51c and the second joint portion 53c, making it easy to secure an insulating distance between the first joint portion 51c and the second joint portion 53c. This eliminates the need to additionally arrange a member to insulate the first joint portion 51c and the second joint portion 53c, thus suppressing an increase in the number of parts in the power converter 10. Consequently, it is possible to more effectively suppress an increase in the manufacturing cost and manufacturing man-hours of the power converter 10.

[0080] As shown in Figure 7, the second output section 53e is plate-shaped and protrudes to the right (-D1 side) from the lower end of the second main body 53a. The plate surface of the second output section 53e faces the second direction D2. A hole is provided in the second output section 53e. The hole is a hole that penetrates the second output section 53e in the second direction D2. In this embodiment, the second busbar 53 has three second output sections 53e. Each second output section 53e is spaced apart from each other along the third direction D3. Viewed from the first direction D1, each second output section 53e is positioned offset from the first output section 51e in the third direction D3. Each second output section 53e is positioned above each other's different negative electrode supply terminals 41c. Viewed from the second direction D2, the holes provided in each second output section 53e overlap with the female screw holes provided in each of the different negative electrode supply terminals 41c. Bolts (not shown) are passed through holes provided in each second output section 53e, and these bolts are tightened into female threaded holes. In this way, each second output section 53e is connected to a different negative electrode supply terminal 41c. As described above, each first output section 51e is connected to a different positive electrode supply terminal 41a. Therefore, the busbar 50 is electrically connected to the power module 40. As described above, the capacitor module 20 is electrically connected to the busbar 50. In this way, the capacitor module 20 and the power module 40 are electrically connected via the busbar 50. Therefore, the first current C1 smoothed in the capacitor module 20 is supplied to the power module 40.

[0081] The output busbar 61 shown in Figure 2 electrically connects the power module 40 to the lead wires (not shown) of a motor (not shown). This allows a second current C2 to be supplied from the power module 40 to the motor via the output busbar 61. Viewed from a third direction D3, the output busbar 61 is a roughly L-shaped plate. In this embodiment, the output busbar 61 is made of a metallic material such as copper and silver. The output busbar 61 is electrically conductive.

[0082] As shown in Figure 6, the power converter 10 is equipped with a plurality of output busbars 61. In this embodiment, the power converter 10 is equipped with three output busbars 61. The number of output busbars 61 equipped with the power converter 10 may be two or fewer, or four or more. Each output busbar 61 is spaced apart from each other along the third direction D3. Phase currents of different phases flow through each output busbar 61. As shown in Figure 2, each output busbar 61 has a first portion 61a and a second portion 61c.

[0083] The first portion 61a is plate-shaped and extends in the first direction D1. The plate surface of the first portion 61a faces the second direction D2. As shown in Figure 6, the left side (+D1 side) of each first portion 61a is positioned above each other's different output terminals 42. As shown in Figure 2, the left side of each first portion 61a is provided with a hole 61b that penetrates the first portion 61a in the second direction D2. Viewed from the second direction D2, each hole 61b coincides with a hole 42a provided in each of the different output terminals 42. A bolt 96 is passed through each hole 61b in the second direction D2, and each bolt 96 is tightened into each of the different holes 42a. In this way, each first portion 61a is fastened to each of the different output terminals 42. Therefore, each output busbar 61 is electrically connected to the power module 40.

[0084] The second portion 61c is a plate-like structure that extends downward from the right (-D1) end of the first portion 61a. The plate surface of the second portion 61c faces the first direction D1. As shown in Figure 4, the lower portion of each second portion 61c passes through the bottom wall hole 12e of the housing 12 in the second direction D2. As a result, the lower end of each second portion 61c is located outside the housing 11. Lead wires (not shown) of the motor are connected to the lower end of each second portion 61c. This electrically connects the output busbar 61 and the motor. Therefore, the power module 40 and the motor (not shown) are electrically connected via the output busbar 61. As a result, the second current C2 generated by the power module 40 is supplied to the motor.

[0085] As shown in Figure 6, the current sensor 63 is located in the right (+D1) portion inside the housing 12. The current sensor 63 is located to the right of the power module 40. As shown in Figure 2, the current sensor 63 has a resin portion 63a and a sensor portion 63c.

[0086] As shown in Figure 6, the resin portion 63a is a substantially rectangular parallelepiped extending in the third direction D3. As shown in Figure 2, the resin portion 63a holds the output busbar 61 and the sensor portion 63c. The resin portion 63a is made of resin. The resin portion 63a is insulating. In this embodiment, the resin portion 63a is formed by insert molding, with the output busbar 61 and the sensor portion 63c each serving as insert members.

[0087] The sensor unit 63c detects the second current C2 flowing through each output busbar 61. The sensor unit 63c is embedded in the resin unit 63a. Although not shown in the figure, the sensor unit 63c has an annular core unit surrounding the output busbar 61 and a sensor substrate. The core unit is made of a metal material with high magnetic permeability, such as ferrite and permeralloy. The core unit collects the magnetic field generated by the current flowing through the output busbar 61. Three sensors (not shown) are mounted on the sensor substrate. The sensor substrate is also electrically connected to the control board 80. Each sensor detects the magnetic field generated by the current flowing through the output busbar 61. The sensors are, for example, Hall ICs. The sensors convert the magnetic field into a voltage and output it. As a result, each sensor detects the current value of the second current C2 flowing through each output busbar 61. The sensor substrate transmits the current value of the second current C2 flowing through the output busbar 61 detected by each sensor to the control board 80.

[0088] As shown in Figure 2, the control board 80 is a plate-shaped structure that extends in a direction perpendicular to the second direction D2. The control board 80 is located to the right (-D1 side) of the capacitor module 20. The control board 80 is located below the power module 40. The control board 80 is electrically connected to the power board 40a via cables (not shown). As described above, the control board 80 is electrically connected to the sensor part 63c of the current sensor 63. The control board 80 is also electrically connected to a main control unit (not shown) of the vehicle, etc., via a connector part 81 attached to the bottom wall part 12d. The control board 80 controls the operation of multiple switching elements mounted on the power board 40a based on the target value of the second current C2 included in the control signal transmitted from the main control unit, and the current value flowing through each output busbar 61 detected by the sensor part 63c. In this way, the control board 80 controls the second current C2 supplied from the power module 40 to the motor.

[0089] According to this embodiment, the power conversion device 10 includes a power module 40 that performs power conversion, a capacitor module 20 that is located to the left of the power module 40 (+D1 side), i.e., on one side of the first direction D1 (+D1 side), and electrically connected to the power module 40, and a housing 11 that houses the power module 40 and the capacitor module 20, respectively. The capacitor module 20 has a plurality of capacitor boards 21 on which capacitors 30 are mounted, with the board surface facing the first direction D1, and each of the plurality of capacitor boards 21 is arranged in a line along the first direction D1. Therefore, compared to a configuration in which the board surface of each capacitor board 21 faces a second direction D2 perpendicular to the first direction D1, and each capacitor board 21 is arranged in a line along the second direction D2, the capacitor module 20 can be made smaller in the first direction D1. As a result, the housing 11 can be made smaller in the first direction D1. Therefore, in the first direction D1, that is, the direction in which the power module 40 and the capacitor module 20 are arranged side by side, the power converter 10 can be miniaturized. This increases the degree of freedom in the space available for mounting the power converter 10 in vehicles and the like.

[0090] Although embodiments of the present invention have been described above, the configurations and combinations thereof in the embodiments are merely examples, and additions, omissions, substitutions, and other modifications are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited by the embodiments.

[0091] The power module and capacitor module may be connected directly without using busbars. In this case, busbars are unnecessary, thus preventing an increase in the number of components in the power converter. Therefore, it is possible to suppress an increase in the manufacturing cost and labor of the power converter.

[0092] The power converter of this embodiment is not limited to generating current supplied to a motor that drives a vehicle, but may also generate current supplied to a drive device such as a motor mounted on an electrical appliance. Furthermore, the power converter may be an inverter that generates alternating current of a predetermined waveform from a direct current supplied from an external power source, or a converter that generates direct current from an alternating current supplied from an external power source.

[0093] Furthermore, this technology can take the following configuration: (1) A power conversion device comprising a power module that performs power conversion, a capacitor module that is positioned on one side of the power module in the first direction and is electrically connected to the power module, and a housing that houses the power module and the capacitor module, wherein the capacitor module has a plurality of capacitor boards on which capacitors are mounted and whose board surfaces face the first direction, and each of the plurality of capacitor boards is arranged in a line along the first direction. (2) The power conversion device according to (1), further comprising a fixing member fixed to the housing, wherein each of the plurality of capacitor boards has a fixing terminal portion protruding to one side in a second direction intersecting the first direction, the capacitor module has a connecting member that contacts each of the adjacent fixing terminal portions in the first direction, the connecting member is provided with a through hole penetrating in the first direction, the fixing terminal portion is provided with a hole penetrating the fixing terminal portion in the first direction, the fixing member is provided with a fixing hole portion recessed on one side in the first direction and having a female screw formed on its inner circumferential surface, and the connecting member and the fixing terminal portion are each fixed to the fixing member by a fastening member that passes through the through hole and the hole portion and is tightened into the fixing hole portion. (3) The power conversion device according to (2), wherein the fixing member is made of resin and the connecting member is conductive. (4) The power conversion device according to (2) or (3), comprising a busbar for electrically connecting the power module and the capacitor module, wherein each of the plurality of capacitor boards has a junction terminal portion that protrudes to the other side in the second direction and is joined to the busbar. (5) The power conversion device according to (4), comprising a plurality of busbars including a first busbar and a second busbar, wherein each of the plurality of capacitor boards has a plurality of junction terminal portions including a first junction terminal portion and a second junction terminal portion, the first busbar has a first junction portion that is joined to the first junction terminal portion, the second busbar has a second junction portion that is joined to the second junction terminal portion, and the first junction portion and the second junction portion are each positioned offset from each other in the second direction.(6) The power conversion device according to (5), wherein an insulating sheet member is disposed between the first busbar and the second busbar. (7) The power conversion device according to any one of (1) to (6), wherein each of the plurality of capacitor boards has a plurality of capacitors mounted on it, and in each of the plurality of capacitor boards, the plurality of capacitors are arranged in a line along a second direction intersecting the first direction and a third direction intersecting both the first and second directions. (8) The power conversion device according to any one of (1) to (7), wherein the capacitor board located on the far other side of the plurality of capacitor boards has an input terminal protruding in a direction perpendicular to the first direction.

[0094] 10...Power converter, 11...Housing, 20...Capacitor module, 21...Capacitor board, 21b...Fixed terminal section, 21d...Joining terminal section, 21e...Input terminal, 24c, 25c...Hole section, 24d...First joining terminal section, 25d...Second joining terminal section, 30...Capacitor, 33...Connecting member, 33a...Through hole, 35...Fixing member, 35c...Fixing hole section, 40...Power module, 50...Bus bar, 51...First bus bar, 51c...First joining section, 53...Second bus bar, 53c...Second joining section, 91...Fastening member, D1...First direction, D2...Second direction

Claims

1. A power conversion device comprising: a power module that performs power conversion; a capacitor module disposed on one side of the power module in a first direction and electrically connected to the power module; and a housing that houses the power module and the capacitor module, wherein the capacitor module has a plurality of capacitor boards on which capacitors are mounted and whose board surfaces face the first direction, and each of the plurality of capacitor boards is arranged in a line along the first direction.

2. The power conversion device according to claim 1, comprising a fixing member fixed to the housing, each of the plurality of capacitor boards having a fixing terminal portion protruding to one side in a second direction intersecting the first direction, the capacitor module having a connecting member that contacts each of the adjacent fixing terminal portions in the first direction, the connecting member having a through hole penetrating in the first direction, the fixing terminal portion having a hole penetrating through the fixing terminal portion in the first direction, the fixing member having a fixing hole portion recessed on one side in the first direction with a female screw formed on its inner circumferential surface, and the connecting member and the fixing terminal portion each being fixed to the fixing member by a fastening member that passes through the through hole and the hole and is tightened into the fixing hole portion, respectively.

3. The power conversion device according to claim 2, wherein the fixing member is made of resin and the connecting member is conductive.

4. The power conversion device according to claim 2 or 3, comprising a busbar for electrically connecting the power module and the capacitor module, wherein each of the plurality of capacitor boards has a connecting terminal portion that protrudes to the other side in the second direction and is joined to the busbar.

5. The power conversion device according to claim 4, comprising a plurality of busbars including a first busbar and a second busbar, each of the plurality of capacitor substrates having a plurality of connection terminals including a first connection terminal and a second connection terminal, the first busbar having a first connection portion that is connected to the first connection terminal, the second busbar having a second connection portion that is connected to the second connection terminal, and each of the first and second connection portions being positioned offset from each other in the second direction.

6. The power conversion device according to claim 5, wherein an insulating sheet member is disposed between the first busbar and the second busbar.

7. The power conversion device according to any one of claims 1 to 3, wherein each of the plurality of capacitor boards is mounted with a plurality of capacitors, and in each of the plurality of capacitor boards, the plurality of capacitors are arranged in a line along a second direction intersecting the first direction and a third direction intersecting both the first and second directions.

8. The power conversion device according to any one of claims 1 to 3, wherein the capacitor board located on the other side of the first direction among the plurality of capacitor boards has an input terminal protruding in a direction perpendicular to the first direction.

Images