CN112042102A

CN112042102A - Power conversion device

Info

Publication number: CN112042102A
Application number: CN201980027844.6A
Authority: CN
Inventors: 小岛和成; 田中纪博; 后藤贵昭
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2018-04-25
Filing date: 2019-04-19
Publication date: 2020-12-04
Anticipated expiration: 2039-04-19
Also published as: JP6908061B2; DE112019002162T5; JP2019195250A; CN112042102B

Abstract

A power conversion device (1) is provided with a heat generating component (5), and a first capacitor module (3) and a second capacitor module (4) which are arranged to face each other with the heat generating component (5) therebetween. The first capacitor module (3) has: a first capacitor element (31); a first case (32) that houses a first capacitor element (31); and a first bus bar (33) having one end connected to the first capacitor element (31). The second capacitor module (4) has: a second capacitor element (41); a second case (42) that houses a second capacitor element (41); and a second bus bar (43) having one end connected to the second capacitor element (41). The second bus bar (43) has an intervening section (431) interposed between the second capacitor element (41) and the heat generating component (5) in a spaced state.

Description

Power conversion device

Citation of related applications

The present application is based on the japanese patent application No. 2018-84046 applied on 25/4/2018 and the japanese patent application No. 2019-12926 applied on 29/1/2019, the contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to a power conversion apparatus.

Background

For example, a power conversion device such as an inverter mounted in an electric vehicle, a hybrid vehicle, or the like includes a switching circuit unit and a capacitor module. Patent document 1 discloses a power conversion device in which a plurality of capacitor modules are arranged. This makes it easy to save space while increasing the capacity of the entire capacitor. Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2009-111435

Disclosure of Invention

When a plurality of capacitor modules are arranged, it is necessary to design in consideration of thermal damage to capacitor elements in the capacitor modules. That is, although the power conversion device is provided with a heat generating component such as a discharge resistor in addition to the capacitor module, it is necessary to suppress heat damage from the heat generating component to the capacitor element. On the other hand, in view of downsizing of the power conversion device and the like, the positional relationship between the plurality of capacitor modules and the heat generating component is also restricted.

The present disclosure provides a power conversion device capable of suppressing the second capacitor element from receiving heat from a heat generating component and realizing miniaturization.

One aspect of the present disclosure is a power conversion apparatus having: a heat generating component; and a first capacitor module and a second capacitor module disposed opposite to each other with the heat generating component interposed therebetween,

the first capacitor module includes: a first capacitor element; a first case that accommodates the first capacitor element; and a first bus bar having one end connected to the first capacitor element,

the second capacitor module includes: a second capacitor element; a second case that accommodates the second capacitor element; and a second bus bar having one end connected to the second capacitor element,

the second bus bar has an intervening portion interposed between the second capacitor element and the heat generating component in a spaced state.

In the power conversion device, the second bus bar has an intervening portion interposed between the second capacitor element and the heat generating component in a state of being spaced apart from the two. Thus, the heat from the heat generating component to the second capacitor element can be blocked by the interposed portion of the second bus bar. As a result, the temperature rise of the second capacitor element can be suppressed.

The intermediate portion for blocking the heat from moving is a part of the second bus bar. Therefore, the temperature rise of the second capacitor element can be suppressed without particularly increasing the number of components. Therefore, the power conversion device can also be downsized.

As described above, according to the above aspect, it is possible to provide a power conversion apparatus capable of suppressing the second capacitor element from receiving heat from the heat generating component and realizing miniaturization.

Drawings

The above objects, other objects, features and advantages of the present disclosure will become more apparent with reference to the accompanying drawings and the following detailed description. The drawings are as follows.

Fig. 1 is a top explanatory view of a power converter in embodiment 1.

Fig. 2 is a top explanatory view of the power converter in embodiment 1, as viewed from the side opposite to fig. 1.

Fig. 3 is a cross-sectional view of the first capacitor module and the second capacitor module of embodiment 1, as viewed from the Z direction, and corresponds to a cross-sectional view taken along line III-III of fig. 4.

Fig. 4 is a cross-sectional view along line IV-IV of fig. 3.

Fig. 5 is a perspective view of a first capacitor module in embodiment 1.

Fig. 6 is a view of fig. 5 with the VI-VI line vertically reversed in a cross-sectional view.

Fig. 7 is a sectional perspective view of a second capacitor module in embodiment 1.

Fig. 8 is a circuit diagram of the power conversion device in embodiment 1.

Fig. 9 is a top explanatory view of the power converter in embodiment 2.

Fig. 10 is a cross-sectional view taken along line a-a of fig. 9.

Fig. 11 is a perspective view of a power conversion device in embodiment 2.

Fig. 12 is a cross-sectional explanatory view of the power conversion device in embodiment 3.

Detailed Description

(embodiment mode 1)

An embodiment of the power conversion device will be described with reference to fig. 1 to 8. As shown in fig. 1 and 2, the power conversion device 1 of the present embodiment includes a discharge resistor 5, a first capacitor module 3, and a second capacitor module 4 as heat generating components. As shown in fig. 3 and 4, the first capacitor module 3 and the second capacitor module 4 face each other with the discharge resistor 5 interposed therebetween.

As shown in fig. 3 to 6, the first capacitor module 3 includes a first capacitor element 31, a first case 32, and a first bus bar 33. The first case 32 accommodates the first capacitor element 31. One end of the first bus bar 33 is connected to the first capacitor element 31.

As shown in fig. 3, 4, and 7, the second capacitor module 4 includes a second capacitor element 41, a second case 42, and a second bus bar 43. Second case 42 accommodates second capacitor element 41. One end of the second bus bar 43 is connected to the second capacitor element 41.

As shown in fig. 3 and 4, second bus bar 43 has an interposed portion 431 interposed between second capacitor element 41 and discharge resistor 5 in a state of being spaced apart from both. That is, intermediate portion 431 is disposed between second capacitor element 41 and discharge resistor 5, but is spaced apart from both second capacitor element 41 and discharge resistor 5. That is, in the arrangement direction of second capacitor element 41 and discharge resistor 5, gaps are provided between second capacitor element 41 and intermediate portion 431 and between intermediate portion 431 and discharge resistor 5.

As shown in fig. 1, 2, and 6, the first bus bar 33 has a terminal connection portion 332 connected to the power terminal 21 of the switch circuit portion 20. The switching circuit unit 20 includes a semiconductor module 2 and a cooler 220 for cooling the semiconductor module 2. The cooler 220 is constituted by a plurality of cooling pipes 22. Then, the cooling pipe 22 cools the semiconductor module 2 by thermally contacting the semiconductor module 2.

The power conversion device 1 of the present embodiment is mounted on a vehicle such as an electric vehicle or a hybrid vehicle, and is connected between a dc power supply BAT and an ac rotating electrical machine MG as shown in a circuit diagram of fig. 8. Then, the power conversion device 1 is configured to be capable of performing power conversion between dc power and ac power by the switching action of the switching circuit portion 20.

The switching circuit unit 20 includes a plurality of semiconductor modules 2 each having a

switching element

2u or 2 d. As shown in fig. 1 and 2, the plurality of semiconductor modules 2 are stacked together with the plurality of cooling pipes 22. The cooling pipe 22 has a coolant flow path therein. The plurality of cooling pipes 22 connect the refrigerant flow paths to each other, thereby configuring the cooler 220.

Each semiconductor module 2 has the power terminal 21 protruding in a direction orthogonal to the stacking direction X. The terminal connection portions 332 of the first bus bar 33 of the first capacitor module 3 are connected to these power terminals 21. Hereinafter, the stacking direction X is also referred to as the X direction. The projecting direction of the power terminal 21 is appropriately referred to as a Z direction, and a direction orthogonal to both the X direction and the Z direction is appropriately referred to as a Y direction.

The plurality of semiconductor modules 2 are arranged at positions aligned in the Y direction with respect to the first capacitor module 3. The first capacitor module 3 has a long shape in the X direction. In a region substantially halfway in the longitudinal direction, the stacked body of the semiconductor module 2 (i.e., the switching circuit section 20) faces the first capacitor module 3 in the Y direction. The first capacitor module 3 has an opening 321 of the first case 32 facing the switching circuit unit 20 in the Y direction. That is, the casting surface (i.e., the first resin surface 341) of the first sealing resin 34 faces the switching circuit portion 20 side in the Y direction.

As shown in fig. 8, each semiconductor module 2 incorporates, as switching elements, an upper arm switching element 2u and a lower arm switching element 2d connected in series with each other. Then, the high potential side of the upper arm switching element 2u is connected to the positive power terminal 21, and the low potential side of the lower arm switching element 2d is connected to the negative power terminal 21. A connection portion between the upper arm switching element 2u and the lower arm switching element 2d is connected to an output ac terminal not shown. The ac terminal is connected to the rotating electrical machine MG.

As shown in fig. 1, 5, 6, and 8, first bus bar 33 includes positive first bus bar 33P and negative first bus bar 33N connected to the electrodes of first capacitor element 31 on the opposite sides to each other. The terminal connection portion 332 of the positive first bus bar 33P is connected to the positive power terminal 21, and the terminal connection portion 332 of the negative first bus bar 33N is connected to the negative power terminal 21.

The first bus bar 33 has a power supply connection unit 333 as a connection unit on the dc power supply BAT side. The power supply connection portion 333 of the positive first bus bar 33P is electrically connected to the positive electrode of the dc power supply BAT, and the power supply connection portion 333 of the negative first bus bar 33N is electrically connected to the negative electrode of the dc power supply BAT.

As shown in fig. 1 and 2, the second capacitor module 4 is connected to the power supply connection part 333 of the first bus bar 33. Thereby, as shown in fig. 8, the first capacitor module 3 and the second capacitor module 4 are connected in parallel with each other. As shown in fig. 2, the second capacitor module 4 is detachably fixed to the power supply connection portion 333 by the fastening member 11.

As shown in fig. 1 and 2, the second capacitor module 4 is arranged so as to be aligned in the Y direction with respect to the first capacitor module 3, and is arranged so as to be aligned in the X direction with respect to the switch circuit section 20. As shown in fig. 3 and 4, the discharge resistor 5 is disposed between the first capacitor module 3 and the second capacitor module 4 in the Y direction. Then, the interposed portion 431 of the second bus bar 43 is interposed between the discharge resistor 5 and the second capacitor 41.

In this embodiment, the discharge resistor 5 is a member (not shown) in which a discharge resistor element is mounted on a substrate. As shown in fig. 3 to 5, the normal direction of the discharge resistor 5 (i.e., the normal direction of the substrate) is oriented in the Y direction. As shown in fig. 8, the discharge resistor 5 is connected in parallel with the first capacitor module 3 and the second capacitor module 4. Thereby, it is configured to be able to discharge the electric charges charged in the first capacitor module 3 and the second capacitor module 4 from the discharge resistance 5.

As shown in fig. 3, 4, and 7, the second capacitor module 4 also incorporates a second capacitor element 41 in a second case 42, as in the first capacitor module 3. Second capacitor element 41 is sealed with second sealing resin 44 in second case 42. The second case 42 faces the opening 421 toward the first capacitor module 3 in the Y direction. That is, the second capacitor module 4 faces the second resin surface 441 of the second sealing resin 44 toward the first capacitor module 3 in the Y direction. As shown in fig. 3, the first capacitor module 3 also has a plurality of first capacitor elements 31, and the second capacitor module 4 also has a plurality of second capacitor elements 41.

The second capacitor module 4 has a pair of second bus bars 43 connected to a pair of electrodes of the second capacitor element 41, respectively. These second bus bars 43 extend on the outer side surface of the second case 42. The positive-electrode-side second bus bar 43P projects from the opening surface 421 of the second case 42 and extends to the outer surface of the second case 42. Although not shown in fig. 7, the second bus bar 43N on the negative electrode side similarly protrudes from the opening surface 421 and extends to the outer surface of the second case 42. As shown mainly by a broken line in fig. 2, the second bus bar 43N has a Y-direction extending portion 43Ny that overlaps the second bus bar 43P on the positive electrode side in the thickness direction and extends in the Y direction while maintaining insulation from the second bus bar 43P. The second bus bar 43N has an X-direction extending portion 43Nx, and the X-direction extending portion 43Nx is overlapped with and connected to a part of the Y-direction extending portion 43Ny, and is disposed on the outer surface of the second housing 42 so as to extend in the X direction. In this embodiment, the Y-direction extending portion 43Ny and the X-direction extending portion 43Nx are formed by different members.

As shown in fig. 2 and 8, the power supply connection part 333 of the first bus bar 33 is connected to the dc power supply BAT via the second bus bar 43. That is, the second bus bar 43 has an inverter-side connecting portion 432 connected to the first bus bar 33 at one end portion. The inverter-side connecting portion 432 is connected to the power supply connecting portion 333 of the first bus bar 33 by the fastening member 11. A power supply side connection portion 433 to which a connection wire from the dc power supply BAT is connected is formed at the other end portion of the second bus bar 43.

As shown in fig. 1 and 2, the power conversion device 1 includes a device case 12 that houses the switching circuit unit 20, the first capacitor module 3, and the second capacitor module 4. As shown in fig. 1, the first capacitor module 3 is fixed to the device case 12 by a fixing member 133. As shown in fig. 2, the second capacitor module 4 is fixed to the device case 12 by a fixing member 135.

The fixing direction of the fixing member 135 that fixes the second capacitor module 4 and the fixing direction of the fastening member 11 are the same as each other. That is, the fixing member 135 and the fastening member 11 are fastened in a direction from the surface toward the back surface of the paper surface in fig. 2. On the other hand, as shown in fig. 1, the fixing member 133 fixing the first capacitor module 3 is formed in a fixing direction opposite to the fixing member 135 and the fastening member 11.

In this embodiment, the fastening member 11 and the fixing

members

133 and 135 may be formed of bolts.

As described above, the first capacitor module 3 has the positive first bus bar 33P and the negative first bus bar 33N as the first bus bar 33. As shown in fig. 5 and 6, the positive first bus bar 33P and the negative first bus bar 33N have facing portions 335 arranged to face each other in the thickness direction with an insulating layer 336 interposed therebetween. The insulating layer 336 is made of a resin molded body. The plurality of terminal connection portions 332 protrude from the opposing portion 335 on the side opposite to the first capacitor element 31 in the Y direction.

As shown in fig. 3 to 5, the discharge resistor 5 is mounted on the first capacitor module 3. In this embodiment, the first capacitor module 3 is provided with the discharge resistor 5 in a part of the region where the first bus bar 33 does not protrude in the X direction. The discharge resistor 5 is electrically connected to the first capacitor element 31 within the first capacitor module 3.

The discharge resistor 5 is fixed to the first case 32 and the like by fixing members such as bolts, which are not shown.

The first capacitor module 3 includes a first sealing resin 34 that seals the first capacitor element 31 in the first case 32. The first sealing resin 34 has a first resin surface 341 exposed to the opening surface 321 of the first casing 32. The second capacitor module 4 includes a second sealing resin 44 sealing the second capacitor element 41 in the second case 42. The second sealing resin 44 has a second resin surface 441 exposed to the opening surface 421 of the second case 42. The first capacitor module 3 and the second capacitor module 4 are arranged such that the first resin surface 341 and the second resin surface 441 face each other. The discharge resistor 5 is disposed between the first resin surface 341 and the second resin surface 441.

The substrate of the discharge resistor 5 is disposed substantially parallel to the first resin surface 341 and the second resin surface 441. As shown in fig. 3 to 6, the first resin surface 341 is receded toward the first capacitor element 31 side from the opening surface 321 of the first case 32 (i.e., the end portion of the first case 32 on the second capacitor module 4 side). As shown in fig. 3, 4, and 7, the second resin surface 441 is set back toward the second capacitor element 41 side from the opening surface 421 of the second case 42 (i.e., the end portion of the second case 42 on the first capacitor module 3 side).

At least a part of the interposed portion 431 is disposed outside the second sealing resin 44. As shown in fig. 4 and 7, in the present embodiment, the interposed portion 431 includes an embedded interposed portion 431a embedded in the second sealing resin 44 and an exposed interposed portion 431b exposed from the second sealing resin 44. In the present embodiment, the interposed portion 431 is formed by a part of the second bus bar 43P on the positive electrode side.

The second bus bar 43P on the positive electrode side has an element connecting portion 434, an external terminal portion 435, and an intervening portion 431 formed therebetween.

The element connection portion 434 is a portion connected to the positive electrode of the second capacitor element 41, and the main surface faces in the Z direction. The external terminal portion 435 is disposed on the outer surface of the second housing 42. External terminal portions 435 are located on the opposite side of element connecting portions 434 in the Z direction with second capacitor element 41 therebetween. Then, the main surface of the external terminal portion 435 also faces the Z direction.

The embedding interposed portion 431a extends in the Z direction from an end edge of the element connecting portion 434 on the side closer to the second resin surface 441. The exposed interposed portion 431b extends in the Z direction from an edge of the external terminal portion 435 on the first capacitor module 3 side. The main surfaces of the embedded intermediate portion 431a and the exposed intermediate portion 431b are both arranged facing the Y direction. The embedded intermediate portion 431a and the exposed intermediate portion 431b are connected by a connecting portion 431c having a principal surface facing in the Z direction. The coupling portion 431c protrudes from the second resin surface 441 in the Y direction.

A second sealing resin 44 is interposed between the embedding interposed portion 431a and the second capacitor element 41 in close contact therewith. A space is provided between the exposed interposed portion 431b and the second resin surface 441.

As shown in fig. 4, first bus bar 33 of first capacitor module 3 includes an interposed portion 331 interposed between first capacitor element 31 and discharge resistor 5 in a state of being spaced apart from both of them.

That is, the interposed portion 331 of the first bus bar 33 is disposed between the first capacitor element 31 and the discharge resistor 5, but is spaced apart from both the first capacitor element 31 and the discharge resistor 5. That is, in the arrangement direction (i.e., Y direction) of first capacitor element 31 and discharge resistor 5, gaps are provided between first capacitor element 31 and intervening portion 331, and between intervening portion 331 and discharge resistor 5.

In the present embodiment, the interposed portion 331 is formed by a part of the first bus bar 33N on the negative electrode side. The first bus bar 33N on the negative electrode side has an element connection portion 337 connected to the negative electrode of the first capacitor element 31. The negative electrode of the first capacitor element 31 is provided on the surface opposite to the opening 321 of the first case 32 in the Y direction. The first bus bar 33N has an intermediate portion 338 extending from the element connecting portion 337 toward the opening face 321 side of the first case 32. An interposed portion 331 is formed to extend in the Z direction from an edge on the opening surface 321 side of the intermediate portion.

The interposed portion 331 is embedded in the first sealing resin 34. The first sealing resin 34 is filled between the interposed portion 331 and the first capacitor element 31 in a state of being in close contact therewith.

In addition, as described above, as shown in fig. 1 and 2, the first capacitor module 3 is connected to the semiconductor module 2 cooled by the cooler 220 at the first bus bar 33. Therefore, the first capacitor module 3 is relatively easy to dissipate heat, and is relatively easy to suppress temperature rise. Further, since the first bus bar 33 is disposed close to the cooler 220, heat dissipation of the first capacitor module 3 is also easily promoted.

On the other hand, since the second capacitor module 4 is distant from the cooler 220 in the heat transfer path via the second bus bar 43, the first bus bar 33, and the semiconductor module 2, it is relatively difficult to dissipate heat compared to the first capacitor module 3. Further, the second bus bar 43 of the second capacitor module 4 also serves as an input line through which an input current from the dc power supply BAT flows, and therefore, the temperature is likely to rise. Therefore, in the present embodiment, if heat reception from the discharge resistor 5 is performed equally, the second capacitor module 4 is likely to be at a higher temperature than the first capacitor module 3.

Further, as shown in fig. 2, the power conversion device 1 has a bus bar connection portion 110 in which the first bus bar 33 and the second bus bar 43 are connected to each other. The power converter 1 further includes a cooling body that cools the components thereof. In this embodiment, the cooling body is the cooler 220 described above. That is, the cooling body is a cooler 220 that cools the semiconductor module 2 that is a component of the power conversion device 1. The bus bar connecting portion 110 is configured to be able to dissipate heat generated in the bus bar connecting portion 110 to the cooler 220.

That is, the bus bar connecting portion 110 is disposed near the cooler 220. Thereby, it is configured that the bus bar connecting portion 110 can be cooled by the cooler 220. For example, no heat generating member such as an electronic component is disposed between the cooler 220 and the bus bar connecting portion 110. The bus bar connecting portion 110 is disposed, for example, at a position closer to the cooler 220 than the center of the second casing 42.

In this embodiment, as described above, the bus bar connecting portion 110 is a fastening portion fastened by the fastening member 11 such as a bolt. However, the bus bar connecting portion 110 may be a welded portion formed by welding or the like.

At least a part of the cooling body is disposed between the bus bar connecting portion 110 and the semiconductor module 2. The cooling body (i.e., the cooler 220) has a plurality of refrigerant channels 221. The plurality of coolant flow paths 221 are stacked together with the semiconductor modules 2 to form the stacked body 200. The coolant flow field 221r disposed at one end of the stacked body 200 in the stacking direction is disposed between the semiconductor module 2 and the bus bar connecting portion 110 in the stacking direction.

In this embodiment, the cooling pipe 22r disposed at one end of the cooler 220 in the X direction is disposed between the bus bar connecting portion 110 and the semiconductor module 2. That is, the coolant flow path 221r inside the cooling tube 22r is disposed between the bus bar connecting portion 110 and the semiconductor module 2.

In other words, the bus bar connecting portion 110 is disposed at a position of the cooling pipe 22r opposite to the side where the semiconductor module 2 is disposed.

Next, the operation and effects of the present embodiment will be described.

In the power conversion device 1, the second bus bar 43 includes an intervening portion 431 interposed between the second capacitor element 41 and the discharge resistor 5 as a heat generating component in a state of being spaced apart from both. Thus, the heat from discharge resistor 5 to second capacitor element 41 can be blocked by intermediate portion 431 of second bus bar 43. As a result, the temperature increase of second capacitor element 41 can be suppressed.

The interposed portion 431 blocking the heat transfer is a part of the second bus bar 43. Therefore, the temperature rise of second capacitor element 41 can be suppressed without particularly increasing the number of components. Therefore, the power conversion device 1 can also be downsized.

Further, the discharge resistor 5 is mounted on the first capacitor module 3. Therefore, the assembly process of the discharge resistor 5 in the power conversion device 1 can be easily performed. In addition, the arrangement space of the discharge resistor 5 is easily reduced, and the power conversion device 1 is easily miniaturized.

The first capacitor module 3 and the second capacitor module 4 are arranged such that the first resin surface 341 and the second resin surface 441 face each other. This makes it easy to secure a space between the first resin surface 341 and the second resin surface 441. That is, an insulating space of air is easily formed between the first capacitor module 3 and the second capacitor module 4. Then, discharge resistor 5 is disposed between first resin surface 341 and second resin surface 441. This facilitates formation of heat insulating spaces between the first capacitor module 3 and the second capacitor module 4, and the discharge resistor 5. As a result, it is easy to suppress the first capacitor element 31 or the second capacitor element 41 from receiving heat from the discharge resistor 5.

At least a part of the interposed portion 431 is disposed outside the second sealing resin 44. That is, the interposed section 431 includes an exposed interposed section 431 b. This makes it easier to release the heat of the interposed portion 431 to the outside. As a result, the temperature rise of second capacitor element 41 can be effectively suppressed.

First bus bar 33 has an intervening portion 331 interposed between first capacitor element 31 and discharge resistor 5 in a state of being spaced apart from both. This also suppresses heat reception from first capacitor element 31 by discharge resistor 5.

In addition, the first bus bar 33 has a terminal connection portion 332 connected to the power terminal 21 of the switch circuit portion 20, and the switch circuit portion 20 has a cooler 220. Therefore, as described above, the first capacitor module 3 relatively easily dissipates heat, and the temperature rise is relatively easily suppressed. Therefore, by providing intermediate portion 431 provided between second capacitor element 41 and discharge resistor 5 as a member having an excellent heat insulating function, thermal damage to second capacitor element 41 can be more effectively suppressed.

The bus bar connection unit 110 is disposed so as to be able to dissipate heat generated in the bus bar connection unit 110 to a cooler, i.e., the cooler 220. This enables the bus bar connecting portion 110, which is particularly likely to generate heat, in the current path to be efficiently cooled. That is, since the resistance value of the bus bar connecting portion 110 is relatively easily increased, joule heat is easily generated. The bus bar connection unit 110, which easily generates a large amount of heat, is disposed in the vicinity of the cooler 220, for example, and is configured to easily dissipate heat to the cooler 220. This can improve heat dissipation of the entire power conversion device 1.

At least a part of the cooler 220, which is a cooling body, is disposed between the bus bar connecting portion 110 and the semiconductor module 2. Thus, in the cooler 220, the bus bar connecting portion 110 can be disposed on the side where the semiconductor module 2 is not disposed. As a result, the bus bar connecting portion 110 can be cooled while the semiconductor module 2 is efficiently cooled.

The coolant flow field 221r disposed at one end of the stacked body 200 is disposed between the semiconductor module 2 and the bus bar connecting portion 110 in the X direction. This enables the bus bar connecting portion 110 to be efficiently cooled. That is, the coolant flow path 221r disposed at one end of the stacked body 200 receives heat of the semiconductor module 2 from only one of the two side surfaces in the X direction. Therefore, the temperature of the refrigerant in the refrigerant flow path 221r is relatively low, and the cooling capacity is high. Therefore, by disposing the bus bar connecting portion 110 close to the coolant flow path 221r, heat can be efficiently dissipated from the bus bar connecting portion 110.

As described above, according to the present embodiment, it is possible to provide a power conversion device that can suppress the second capacitor element from receiving heat from the heat generating component and can be miniaturized.

(embodiment mode 2)

As shown in fig. 9 to 11, this embodiment is a mode for more specifically illustrating the positional relationship and the like of the laminated body 200 and the second capacitor module 4.

At least one of the first capacitor module 3 and the second capacitor module 4 is a cooling body opposing module disposed opposite to the cooling body. Then, the bus bar connecting portion 110 is disposed in the housing of the cooling body opposing module.

In the present embodiment, the second capacitor module 4 is a cooling body opposing module, as shown in fig. 9 and 10. Therefore, the bus bar connecting portion 110 is disposed in the second case 42 of the second capacitor module 4.

A pressing member 141 that presses the stacked body 200 is disposed at one end side in the X direction in the stacked body 200. The pressing member 141 is formed of, for example, a plate spring, and is supported by a support portion 142 fixed to a part of the apparatus case 12 (see fig. 1). The pressing member 141 and the supporting portion 142 may be made of metal. In this embodiment, the refrigerant introducing portion 222 and the refrigerant discharging portion 223 that introduce the refrigerant into the cooler 220 are disposed in the cooling pipe 22, and the cooling pipe 22 is disposed at the end portion opposite to the pressing member 141 in the X direction.

The cooler 220 and the second capacitor module 4 constituting the stacked body 200 are arranged to face each other in the X direction. That is, the cooling pipe 22r at one end of the cooler 220 is disposed to face the second capacitor module 4 in the X direction in proximity. However, a pressing member 141 is disposed between the cooling pipe 22r and the second capacitor module 4.

The distance between the cooling pipe 22r and the second capacitor module 4 can be set to, for example, half or less of the size of the second case 42 in the X direction. As shown in fig. 9 to 11, in the second capacitor module 4, a face opposed to the cooling pipe 22r forms one side wall portion in the second case 42. Hereinafter, this side wall portion is referred to as a facing wall portion 422.

The top wall portion 423 facing the Z direction of the bus bar connecting portion 110 in the second housing 42 is disposed in the vicinity of a corner portion with the opposing wall portion 422. That is, the bus bar connecting portion 110 is disposed near the end portion of the top wall portion 423 on the side closer to the stacked body 200.

As shown in fig. 11, a terminal block 424 protruding in the Z direction is provided on the top wall portion 423 of the second case 42 of the second capacitor module 4. The terminal portion of the second bus bar 43 is disposed on the terminal block 424. Then, the terminal portion of the first bus bar 33 (i.e., the power supply connection portion 333) is arranged so as to overlap the terminal portion of the second bus bar 43 (i.e., the inverter-side connection portion 432) arranged on the terminal block 424. Then, the terminal portion of the first bus bar 33 and the terminal portion of the second bus bar 43 are fastened by a fastening member 11 such as a bolt. The fastening portion is a bus bar connecting portion 110. In fig. 10 and the like, the terminal block 424 is omitted.

The other structure is the same as embodiment 1. Note that, unless otherwise specified, of the symbols used in the embodiments 2 and subsequent embodiments, the same symbols as those used in the previous embodiments denote the same components and the like as those in the previous embodiments.

In this embodiment, the bus bar connecting portion 110 is disposed in the second case 42 of the second capacitor module 4, which is a module facing the cooling body disposed to face the cooling body. This enables the bus bar connecting portion 110 to be cooled more efficiently. That is, the second case 42 of the second capacitor module 4 disposed opposite to the cooler 220 is easily cooled by the cooler 220. Therefore, by providing the bus bar connecting portion 110 in the second case 42, the heat of the bus bar connecting portion 110 is easily dissipated through the second case 42.

In addition, in particular, the bus bar connecting portion 110 is provided at a corner portion between the opposing wall portion 422 and the top wall portion 423 of the second housing 42. This shortens the heat transfer distance from the bus bar connecting portion 110 to the opposing wall portion 422, and the bus bar connecting portion 110 can be cooled more efficiently. Otherwise, the same operational effects as those of embodiment 1 are obtained.

(embodiment mode 3)

As shown in fig. 12, this embodiment is a form in which the first bus bar 33 is disposed on the same surface side in the Z direction as both the stacked body 200 and the second capacitor module 4.

The rest is the same as embodiment 2.

In this case, the facing area between the laminated body 200 and the second capacitor module 4 is easily increased. Therefore, the facing area between the facing wall portion 422 of the second capacitor module 4 and the cooling pipe 22r is likely to be large. As a result, the opposing wall 422 is easily cooled, and the bus bar connecting portion 110 disposed in the vicinity of the opposing wall 422 is also easily cooled. Otherwise, the same operational effects as those of embodiment 2 are obtained.

In the above embodiment, the structure in which the discharge resistor is disposed is shown as the heat generating component, but the heat generating component is not particularly limited. Examples of the heat generating component include an electronic component such as a reactor, a temperature sensor (thermistor, etc.), a current sensor, and an electronic circuit board.

In the above embodiment, the intermediate portion 331 is also provided in the first bus bar 33, but the intermediate portion may not be provided in the first bus bar 33. In particular, when second capacitor element 41 is likely to be thermally damaged compared to first capacitor element 31, it may be configured to have intermediate portion 431 of second bus bar 43 and not have intermediate portion 331 of first bus bar 33.

The present disclosure is not limited to the above embodiments, and can be applied to various embodiments without departing from the scope of the present disclosure.

Although the present disclosure has been described in terms of embodiments, it should be understood that the present disclosure is not limited to the embodiments and configurations. The present disclosure also includes various modifications and variations within an equivalent range. In addition, various combinations and modes, including only one element, and one or more or less other combinations and modes also belong to the scope and idea of the present disclosure.

Claims

1. A power conversion device (1) is provided with:

a heat generating component (5); and

a first capacitor module (3) and a second capacitor module (4) disposed opposite to each other with the heat generating component (5) therebetween,

the first capacitor module has: a first capacitor element (31); a first case (32) that houses a first capacitor element (31); and a first bus bar (33) having one end connected to the first capacitor element (31), the second capacitor module having: a second capacitor element (41); a second case (42) that houses a second capacitor element (41); and a second bus bar (43) having one end connected to the second capacitor element,

the second bus bar has an intervening portion (431) interposed between the second capacitor element and the heat generating component in a spaced state.

2. The power conversion apparatus according to claim 1,

the heat generating component is mounted on the first capacitor module.

3. The power conversion apparatus according to claim 1 or 2,

the first capacitor module has a first sealing resin (34) for sealing the first capacitor element in the first case, the first sealing resin having a first resin surface (341) exposed to an opening surface (321) of the first case, the second capacitor module has a second sealing resin (44) for sealing the second capacitor element in the second case, the second sealing resin having a second resin surface (441) exposed to an opening surface (421) of the second case, the first capacitor module and the second capacitor module are disposed so that the first resin surface and the second resin surface face each other, and the heat generating component is disposed between the first resin surface and the second resin surface.

4. The power conversion apparatus according to claim 3,

at least a part of the interposed portion is disposed outside the second sealing resin.

5. The power conversion apparatus according to any one of claims 1 to 4,

the first bus bar has an intervening portion (331) interposed between the first capacitor element and the heat generating component in a spaced state.

6. The power conversion apparatus according to any one of claims 1 to 5,

the first bus bar has a terminal connection part (332) connected to a power terminal (21) of a switching circuit part (20) having a semiconductor module (2) and a cooler (220) that cools the semiconductor module.

7. The power conversion apparatus according to any one of claims 1 to 6,

the power conversion device is provided with a bus bar connecting part (110) for connecting the first bus bar and the second bus bar, and a cooling body (220) for cooling the components of the power conversion device, wherein the bus bar connecting part is configured to radiate heat generated in the bus bar connecting part to the cooling body.

8. The power conversion apparatus according to claim 7,

the cooling body is configured to cool a semiconductor module (2), and at least a part of the cooling body is arranged between the bus bar connecting portion and the semiconductor module.

9. The power conversion apparatus according to claim 8,

the cooling body has a plurality of coolant flow paths (221) that are stacked together with the semiconductor modules to form a stacked body (200), and the coolant flow path that is disposed at one end in the stacking direction in the stacked body is disposed between the semiconductor modules and the bus bar connecting portion in the stacking direction.

10. The power conversion apparatus according to any one of claims 7 to 9,

at least one of the first capacitor module and the second capacitor module is a cooling body opposing module disposed to face the cooling body, and the bus bar connecting portion is provided in a case of the cooling body opposing module.