JP6923375B2 - Power converter - Google Patents

Description

The present invention relates to an improved technique for a power conversion device.

The power conversion device is arranged between the battery and the motor, for example, and controls the electric power stored in the battery to supply the power to the motor. Power converters mounted on hybrid and electric vehicles, that is, many child units (for example, power modules and reactors) that make up a PCU (power control unit), generate heat, and there is a concern that performance will be impaired due to the effects, so cooling. The structure is essential. Various such cooling techniques have been proposed (for example, Patent Document 1).

The cooling device known in Patent Document 1 mounts a power device on a flat housing having a flat upper plate and a lower plate. The housing corresponds to a cooler. The upper plate of the housing is provided with an introduction hole and a discharge hole for the refrigerant. The refrigerant introduction pipe and the refrigerant discharge pipe extend along the upper plate and are formed in a square cross section to close the tip. In the introduction pipe and the discharge pipe, holes are provided on the outer peripheral surface in the vicinity of each tip. These holes are connected to the introduction hole and the discharge hole, respectively. The refrigerant flows downward from the hole on the outer peripheral surface of the horizontal refrigerant introduction pipe, enters the housing through the introduction hole, and flows horizontally through the refrigerant flow path in the housing.

Here, the path of the refrigerant from the tip portion in the refrigerant introduction pipe to the refrigerant flow path of the housing through the introduction hole is referred to as an introduction side refrigerant passage. Further, the path of the refrigerant from the refrigerant flow path of the housing to the tip portion in the refrigerant introduction pipe through the discharge hole is referred to as a discharge side refrigerant passage. The flow direction of the refrigerant flowing through the introduction-side refrigerant passage and the flow direction of the refrigerant flowing through the discharge-side refrigerant passage are significantly different from the flow direction of the refrigerant flowing through the housing. Therefore, the pressure loss of each of the refrigerant passages on the introduction side and the discharge side with respect to the housing is large.

Japanese Unexamined Patent Publication No. 2010-258022

An object of the present invention is to provide a technique capable of reducing the pressure loss of each refrigerant passage on the introduction side and the discharge side with respect to the cooler.

The invention according to claim 1 is a cooler for cooling an electronic component, an introduction-side refrigerant passage for introducing a refrigerant into the cooler, an discharge-side refrigerant passage for discharging a refrigerant from the cooler, and the cooler and the introduction. A housing for accommodating the side refrigerant passage and the discharge side refrigerant passage is provided.
A power conversion device in which the flow direction of the refrigerant flowing through the introduction-side refrigerant passage and the flow direction of the refrigerant flowing through the discharge-side refrigerant passage are different from the flow direction of the refrigerant flowing substantially horizontally through the cooler. In
The lid wherein the the inlet side refrigerant passage and the cooler the discharge-side refrigerant passage, the groove having an open bottom which is closed on the housing, which is attached to the housing while closing the open face of the groove Consists of a department
The depth of the groove from the open surface of the groove is deeper at the position of the introduction side refrigerant passage and the position of the discharge side refrigerant passage than at the position of the cooler.
The lid portion has a protruding portion protruding into the groove portion at each position of the introduction side refrigerant passage and the discharge side refrigerant passage.
This protrusion is a conversion member that changes the flow direction of the refrigerant.
The groove is in a position facing the projecting portions, have a slope portion for converting the flow direction of the refrigerant along the projecting portion,
The protrusion and the slope portion located in the introduction-side refrigerant passage have a configuration in which the flow direction of the refrigerant is obliquely downwardly changed from the introduction-side refrigerant passage toward the cooler.
The protruding portion and the slope portion located in the discharge-side refrigerant passage are characterized in that the flow direction of the refrigerant is obliquely upwardly changed from the cooler toward the discharge-side refrigerant passage. ..

The invention according to claim 2 is characterized in that the shape of the protruding portion is fan-shaped when viewed from the tip end side of the protruding portion.

The invention according to claim 3 is characterized in that the housing and the protruding portion have a positioning portion of the protruding portion with respect to the housing.

The invention according to claim 4 is characterized in that the protruding portion has fins on a surface facing the groove portion to guide the refrigerant flowing through the groove portion.

In the invention according to claim 1, the "introduction side refrigerant passage" that introduces the refrigerant into the cooler and the "discharge side refrigerant passage" that discharges the refrigerant from the cooler are a groove portion and a lid portion that closes the open surface of the groove portion. It consists of. The flow direction of the refrigerant flowing through the introduction-side refrigerant passage and the discharge-side refrigerant passage can be changed by the protrusion protruding from the lid to the inside of the groove and the slope portion provided in the groove along the protrusion. ..

Therefore, the flow directions of the refrigerant on the introduction side and the discharge side with respect to the cooler can be matched with the flow direction of the refrigerant flowing through the cooler to make the flow smooth. As a result, the pressure loss in each of the refrigerant passages on the introduction side and the discharge side with respect to the cooler can be reduced as much as possible. The load on the pump of the refrigerant line that sends the refrigerant to the power converter can be reduced. Moreover, since the flow directions of the refrigerant on the introduction side and the discharge side match the flow direction of the refrigerant flowing through the cooler, the flow becomes smooth, so that the refrigerant is less likely to stay in each refrigerant passage and air is prevented in each refrigerant passage. Accumulation is unlikely to occur. The cooling efficiency of the cooler can be increased.

In the invention according to claim 2, the shape of the protruding portion is fan-shaped when viewed from the tip end side of the protruding portion. Therefore, the flow of the refrigerant from the introduction side refrigerant passage to the cooler can be gradually widened according to the cooler. Further, the flow of the refrigerant from the cooler to the discharge side refrigerant passage can be gradually narrowed according to the cooler. It is possible to reduce the retention of the refrigerant in the introduction side refrigerant passage and the discharge side refrigerant passage. As a result, the pressure loss in each of the refrigerant passages on the introduction side and the discharge side with respect to the cooler can be further reduced.

In the invention according to claim 3, the housing and the protruding portion have a positioning portion of the protruding portion with respect to the housing. Therefore, when assembling the protrusion to the housing, the positioning portion can guide the protrusion to the housing to position the protrusion with respect to the housing.

In the invention according to claim 4, the protruding portion has fins on the surface facing the groove portion to guide the refrigerant flowing through the groove portion. Therefore, the flow of the refrigerant from the introduction side refrigerant passage to the cooler and the flow of the refrigerant from the cooler to the discharge side refrigerant passage can be rectified by guiding them with fins. It is possible to further reduce the pressure loss in each of the refrigerant passages on the introduction side and the discharge side with respect to the cooler.

It is a schematic cross-sectional view of the power conversion apparatus according to this invention. It is an exploded view of the power conversion apparatus shown in FIG. It is a detailed view of the main part shown in FIG. 1, (a) is a figure which shows the cross-sectional structure around the introduction side refrigerant passage, (b) is a cross-sectional view along line bb of (a), (c). Is a plan view of the protruding portion shown in (a). It is a modification diagram around the introduction side refrigerant passage shown in FIG. 3, (a) is a view showing the cross-sectional structure around the introduction side refrigerant passage, (b) is the cross-sectional view along line bb of (a). , (C) is a plan view of the protruding portion shown in (a).

A mode for carrying out the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the power conversion device 10 has a housing 20. The housing 20 includes a first cooler 30 that cools the power module 33 and a second cooler 51 that cools the electronic components 57. Hereinafter, the power conversion device 10 will be described in detail.

The housing 20 is separated into a first chamber 22 and a second chamber 23 by a partition plate 21 integrally formed. For example, the first chamber 22 is located directly above the second chamber 23.

The open end of the first chamber 22 on the opposite side of the partition plate 21 is closed by the refrigerant jacket 30. The refrigerant jacket 30 is a substantially flat member detachably attached to the first chamber 22 by bolts 31, and includes a first cooler 32 inside. A power module 33 is mounted on the outer surface of the refrigerant jacket 30. The first cooler 32 is a refrigerant passage formed in the refrigerant jacket 30 so as to cool the power module 33. The doorway of the first cooler 32 is sealed by sealing members 34, 34 such as an O-ring.

The first child unit 41 is housed in the first room 22. The first child unit 41 includes a base 43 detachably mounted on the partition plate 21 by bolts 42, and an electronic component 44 (for example, a smoothing capacitor, a reactor, a DC-DC converter, a discharge resistor, etc.) mounted on the base 43. ) And. The refrigerant jacket 30 and the power module 33 are covered by the first cover 45. The first cover 45 is detachably attached to the housing 20 by bolts 46.

The second chamber 23 is composed of a groove portion whose side (lower side) opposite to the partition plate 21 is open. Hereinafter, the second chamber 23 will be appropriately referred to as a “groove 23”.

The housing 20 is formed with a flat seating surface 54 along the edge of the open end of the groove 23. The groove portion 23 has an open end opposite to the partition plate 21 closed by a lid portion 53. That is, the lid portion 53 is overlapped with the seat surface 54 and is detachably attached by the bolt 55. The lid portion 53 and the seat surface 54 are sealed by a sealing member 56 such as an O-ring.

The lid portion 53 is provided on a surface 53b (a surface 53b facing the groove 23) opposite to the mounting surface 53a on which electronic components 57, 57 (for example, a smoothing capacitor, a reactor, a DC-DC converter, a discharge resistor, etc.) are mounted. , A plurality of cooling fins 53c are formed. The plurality of cooling fins 53c extend into the groove portion 23. The shape of the cooling fins 53c can be changed simply by replacing the lid portion 53, and the versatility of the power conversion device 10 is increased.

The lid portion 53 and the electronic components 57 and 57 are covered with the second cover 58. The second cover 58 is detachably attached to the housing 20 by bolts 59.

In the housing 20, the refrigerant inlet 61 for introducing the refrigerant from the outside into the second cooler 51, the connecting refrigerant passage 62 for flowing the refrigerant from the second cooler 51 to the first cooler 30, and the first cooler 30 A refrigerant outlet 63 for discharging the refrigerant to the outside is provided. The refrigerant inlet 61 communicates with the second cooler 51 via the introduction-side refrigerant passage 64. The second cooler 51 communicates with the connecting refrigerant passage 62 via the discharge side refrigerant passage 65.

The introduction-side refrigerant passage 64, the second cooler 51, and the discharge-side refrigerant passage 65 are a groove portion 23 provided in the housing 20 and a lid portion 53 attached to the housing 20 while closing the open surface of the groove portion 23. It is a series of refrigerant passages consisting of.

In this way, the housing 20 accommodates the second cooler 51, the introduction side refrigerant passage 64, and the discharge side refrigerant passage 65.

As shown in FIG. 1, the refrigerant (for example, cooling water) supplied from the refrigerant inlet 61 is the introduction side refrigerant passage 64, the second cooler 51, the discharge side refrigerant passage 65, the connection refrigerant passage 62, and the first cooling. It flows through the path of the vessel 32 and is discharged from the refrigerant outlet 63. The refrigerant flowing through the first cooler 32 directly cools the power module 33 through the refrigerant jacket 30. The refrigerant flowing through the second cooler 51 directly cools the electronic component 57 through the plurality of cooling fins 53c and the lid 53. In this way, the first cooler 32 cools the power module 33. The second cooler 51 cools the electronic component 57. Since the first chamber 22 is surrounded by the first cooler 32 and the second cooler 51, the atmospheric temperature in the first chamber 22 can be lowered. Therefore, the electronic component 44 arranged in the first chamber 22 can be indirectly cooled.

By the way, as shown in FIG. 1, the flow direction of the refrigerant flowing through the introduction side refrigerant passage 64 and the flow direction of the refrigerant flowing through the discharge side refrigerant passage 65 are relative to the flow direction Af of the refrigerant flowing through the second cooler 51. Is different.

More specifically, the flow direction Af of the refrigerant flowing inside the second cooler 51 is generally the horizontal direction. The refrigerant inlet 61 is offset upward from the second cooler 51. Therefore, the depth of the groove 23, that is, the depth from the seat surface 54 of the second chamber 23 to the partition plate 21, is deeper at the position of the introduction side refrigerant passage 64 than at the position of the second cooler 51. In this state, the flow direction of the refrigerant flowing from the refrigerant inlet 61 to the second cooler 51 through the introduction side refrigerant passage 64 becomes substantially perpendicular to the flow direction Af of the refrigerant flowing through the second cooler 51, and the pressure becomes high. The loss is large.

Further, the connecting refrigerant passage 62 for flowing the refrigerant from the second cooler 51 to the first cooler 30 extends in a direction substantially perpendicular to the flow direction Af of the refrigerant flowing through the second cooler 51. In this state, the flow direction of the refrigerant flowing from the second cooler 51 to the connecting refrigerant passage 62 through the discharge side refrigerant passage 65 is substantially perpendicular to the flow direction Af of the refrigerant flowing through the second cooler 51. The pressure loss is large.

On the other hand, in the present invention, as shown in FIG. 1, the lid portion 53 has protrusions 71 and 71 protruding into the groove 23 at each position of the introduction side refrigerant passage 64 and the discharge side refrigerant passage 65, respectively. Has. The protrusions 71, 71 are conversion members that change the flow direction of the refrigerant. The groove portion 23 has slope portions 72, 72 that change the flow direction of the refrigerant along the protrusions 71, 71 at a portion facing the protrusions 71, 71.

The protrusion 71 and the slope 72 in the introduction-side refrigerant passage 64 will be described in more detail as a representative. FIG. 3A shows a cross-sectional configuration around the introduction side refrigerant passage. FIG. 3 (b) shows a cross section along the line bb of FIG. 3 (a). FIG. 3C shows the planar configuration of the protrusion shown in FIG. 3A.

As shown in FIGS. 1 to 3, the tip 71a of the protrusion 71 is a flat surface or a pointed tip located near the lower edge of the refrigerant inlet 61. The contour of the protrusion 71 has a shape that is inclined downward from the tip 71a so as to guide the refrigerant introduced from the refrigerant inlet 61 diagonally downward toward the second cooler 51. The contour of the slope portion 72 is an inclined surface along the contour of the protruding portion 71.

As shown in FIGS. 1 and 2, the tip of the protrusion 71 in the discharge-side refrigerant passage 65 is a pointed tip along the edge of the discharge-side refrigerant passage 65.

The above explanation can be summarized as follows. As shown in FIGS. 1 to 3, the protruding portions 71, 71 protruding from the lid portion 53 into the groove portion 23, and the slope portions 72, 72 provided in the groove portion 23 along the protruding portions 71, 71. Therefore, the flow direction of the refrigerant flowing through the introduction side refrigerant passage 64 and the discharge side refrigerant passage 65 can be changed. Therefore, the flow directions of the refrigerant on the introduction side and the discharge side with respect to the second cooler 51 (cooler 51) can be matched with the flow direction Af of the refrigerant flowing through the second cooler 51 to make the flow smooth. .. As a result, the pressure loss in the refrigerant passages 64 and 65 on the introduction side and the discharge side with respect to the second cooler 51 can be reduced as much as possible. It is possible to reduce the load on the pump of the refrigerant line (not shown) for sending the refrigerant to the power conversion device 10.

Moreover, since the flow directions of the refrigerant on the introduction side and the discharge side match the flow direction Af of the refrigerant flowing through the second cooler 51, the flow becomes smooth, so that the refrigerant is unlikely to stay in each refrigerant passage. Air pools are less likely to occur in each refrigerant passage. The cooling efficiency of the second cooler 51 can be increased.

As shown in FIGS. 3A to 3C, the shape of the protruding portion 71 in the introduction-side refrigerant passage 64 is fan-shaped when viewed from the tip 71a side of the protruding portion 71. Therefore, the flow of the refrigerant from the introduction side refrigerant passage 64 to the second cooler 51 can be gradually widened in accordance with the second cooler 51.

Similarly, the shape of the protrusion 71 in the discharge side refrigerant passage 65 shown in FIG. 1 is also fan-shaped when viewed from the tip side of the protrusion 71. Therefore, the flow of the refrigerant from the second cooler 51 to the discharge side refrigerant passage 65 can be gradually narrowed in accordance with the second cooler 51.

It is possible to reduce the retention of the refrigerant in the introduction side refrigerant passage 64 and the discharge side refrigerant passage 65. As a result, the pressure loss of the refrigerant passages 64 and 65 on the introduction side and the discharge side with respect to the second cooler 51 can be further reduced. The plurality of cooling fins 53c extend in the flow direction Af of the refrigerant flowing through the second cooler 51.

<Modification example>
The power conversion device 10A of the modified example will be described with reference to FIGS. 4A to 4C. The power conversion device 10A of the modified example is characterized in that the power conversion device 10 of the embodiment shown in FIGS. 3 (a) to 3 (c) is changed to the configuration shown in FIGS. 4 (a) to 4 (c). The other configurations are the same as those of the power conversion device 10 of the embodiment shown in FIGS. 1 to 3. FIG. 4A corresponds to FIG. 3A. FIG. 4B corresponds to FIG. 3B. FIG. 4 (c) corresponds to FIG. 3 (c).

The housing 20 and the protruding portion 71 in the introduction-side refrigerant passage 64 have positioning portions 81 and 82 of the protruding portion 71 with respect to the housing 20. For example, the housing 20 has a male positioning portion 81, and the protruding portion 71 has a female positioning portion 82. The same applies to the protruding portion 71 in the discharge side refrigerant passage 65 (see FIG. 1). Therefore, when the protrusions 71 and 71 are assembled to the housing 20, the positioning portions 81 and 82 guide the protrusions 71 and 71 to the housing 20 to position the protrusions 71 and 71 with respect to the housing 20. Can be done.

Further, the protrusion 71 in the introduction-side refrigerant passage 64 has a plurality of fins 83 for guiding the refrigerant flowing through the groove 23 on the surface facing the groove 23. The same applies to the protruding portion 71 in the discharge side refrigerant passage 65 (see FIG. 1). Therefore, the flow of the refrigerant from the introduction side refrigerant passage 64 to the second cooler 51 and the flow of the refrigerant from the second cooler 51 toward the discharge side refrigerant passage 65 are guided by the plurality of fins 83 to rectify the rectification. can do. As a result, the pressure loss of the refrigerant passages 64 and 65 on the introduction side and the discharge side with respect to the second cooler 51 can be further reduced.

In the present invention, the power conversion devices 10 and 10A can be mounted on an electric vehicle or a so-called hybrid vehicle, and can also be used for marine or general industry.
Further, the introduction side refrigerant passage 64 and the discharge side refrigerant passage 65 can also serve as a part of the second cooler 51.
The presence or absence of the first cover 45 and the second cover 58 shown in FIG. 1 is arbitrary.

The present invention is suitable for a power conversion device mounted on a vehicle.

10 ... Power converter, 10A ... Power converter, 20 ... Housing, 23 ... Groove (second chamber), 51 ... Cooler (second cooler), 53 ... Lid, 57 ... Electronic components, 64 ... Introduction Side refrigerant passage, 65 ... Discharge side refrigerant passage, 71 ... Protruding part, 71a ... Tip, 72 ... Slope part, 81 ... Male positioning part, 82 ... Female positioning part, 83 ... Fin, Af ... Refrigerant flowing through the second cooler Flow direction.

Claims (4)

A cooler that cools electronic components, an introduction-side refrigerant passage that introduces refrigerant into the cooler, a discharge-side refrigerant passage that discharges refrigerant from the cooler, the cooler, the introduction-side refrigerant passage, and the discharge-side refrigerant. With a housing that accommodates the passage,
A power conversion device in which the flow direction of the refrigerant flowing through the introduction-side refrigerant passage and the flow direction of the refrigerant flowing through the discharge-side refrigerant passage are different from the flow direction of the refrigerant flowing substantially horizontally through the cooler. In
The lid wherein the the inlet side refrigerant passage and the cooler the discharge-side refrigerant passage, the groove having an open bottom which is closed on the housing, which is attached to the housing while closing the open face of the groove Consists of a department
The depth of the groove from the open surface of the groove is deeper at the position of the introduction side refrigerant passage and the position of the discharge side refrigerant passage than at the position of the cooler.
The lid portion has a protruding portion protruding into the groove portion at each position of the introduction side refrigerant passage and the discharge side refrigerant passage.
This protrusion is a conversion member that changes the flow direction of the refrigerant.
The groove is in a position facing the projecting portions, have a slope portion for converting the flow direction of the refrigerant along the projecting portion,
The protrusion and the slope portion located in the introduction-side refrigerant passage have a configuration in which the flow direction of the refrigerant is obliquely downwardly changed from the introduction-side refrigerant passage toward the cooler.
The protruding portion and the slope portion located in the discharge-side refrigerant passage have a configuration in which the flow direction of the refrigerant is obliquely upwardly changed from the cooler toward the discharge-side refrigerant passage.
A power conversion device characterized by the fact that. The power conversion device according to claim 1, wherein the shape of the protruding portion is fan-shaped when viewed from the tip end side of the protruding portion. The power conversion device according to claim 1 or 2, wherein the housing and the protruding portion have a positioning portion of the protruding portion with respect to the housing. The power conversion device according to any one of claims 1 to 3, wherein the protruding portion has fins for guiding the refrigerant flowing through the groove on a surface facing the groove.

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