JP4016907B2 - Power converter - Google Patents

Description

  The present invention relates to a power conversion device including a cooling means for a semiconductor module constituting a power conversion circuit.

Conventionally, a power conversion circuit such as a DC-DC converter circuit or an inverter circuit is sometimes used to generate a drive current for energizing an AC motor that is a power source of an electric vehicle or a hybrid vehicle.
In general, an electric vehicle, a hybrid vehicle, and the like require a large driving current because it is necessary to obtain a large driving torque from an AC motor.
Therefore, in the power conversion circuit that generates the drive current for the AC motor, heat generation from the semiconductor module including the power semiconductor element such as IGBT constituting the power conversion circuit tends to increase.

  Therefore, a large number of flat cooling tubes are arranged between a pair of headers that supply and discharge the cooling medium (refrigerant) so that the plurality of semiconductor modules constituting the power conversion circuit can be cooled with high uniformity. A cooling tube parallel type power converter in which a semiconductor module is sandwiched between cooling tubes has been proposed (see, for example, Patent Document 1).

However, the conventional power conversion device has the following problems. That is, the multilayer laminated structure of the cooling tube and the semiconductor module may be disadvantageous in strength as compared with the single layer structure.
In general, in order to sufficiently secure the strength of the laminated structure, it is necessary to take measures such as increasing the rigidity of the members constituting the laminated structure, that is, the cooling member itself or the semiconductor module itself. If it does so, the enlargement by the thickening of a cooling member etc. and the enlargement by the thickening of a semiconductor module etc. will be caused, and there exists a high possibility that the enlargement of the whole said power converter device and a weight increase will be inevitable.

In particular, in a power conversion device mounted on an electric vehicle, a hybrid vehicle, or the like, the usage environment is severe. In the power converter, it is necessary to sufficiently ensure the structural strength and sufficiently improve the durability.
For this reason, power conversion devices for electric vehicles, hybrid vehicles, and the like have a problem that it is difficult to achieve both improvement in durability and improvement in mountability due to downsizing and weight reduction.
JP 2002-26215 A

  The present invention has been made in view of such conventional problems, and is intended to provide a small-sized and highly durable power conversion device.

The present invention relates to a power conversion device having a semiconductor module that constitutes a power conversion circuit and a cooling tube that forms a flow path of a refrigerant that cools the semiconductor module.
A semiconductor formed by alternately laminating the cooling tube having a flat shape and the flat semiconductor module, and connecting both ends of each cooling tube to a pair of header portions for supplying and discharging the refrigerant. A laminated unit;
A guide unit formed with a pair of guide surfaces arranged with a gap in a predetermined width direction facing a front surface and a back surface formed by side edges along the longitudinal direction of each of the cooling tubes in the semiconductor stacked unit; It is in the power converter device characterized by having (claim 1).

The power conversion device of the present invention includes the guide unit including the guide surface that faces the front surface and the back surface of the semiconductor multilayer unit with a gap in the predetermined width direction.
According to the guide unit, the guide surface facing the front surface and the back surface of the semiconductor multilayer unit regulates the positional variation of the semiconductor multilayer unit, and prevents this when a large positional variation may occur. Can be supported.
In the semiconductor laminated unit, since the rigidity in the short side direction of the laminated surface, that is, the normal direction of the front surface and the back surface may be lowered, the support by the guide surface as described above is effective.

Therefore, in the power converter, the strength of the whole semiconductor stacked unit can be secured by the support structure by the guide unit, and the strength of the entire device can be ensured.
Therefore, in the power converter, the durability and reliability can be sufficiently ensured without increasing the size and weight of the semiconductor multilayer unit itself.
Therefore, the power conversion device of the present invention is a device that has a small size and high durability and excellent quality.

In the present invention, the semiconductor module includes a semiconductor module including a power semiconductor element such as an IGBT element or a MOS FET element.
Further, the guide unit has a groove shape formed along the stacking direction of the semiconductor multilayer unit, and has a pair of recesses arranged so that the opening faces each other, and the semiconductor stack The unit is arranged in a state where both end portions in the longitudinal direction are accommodated in the respective recesses, and the guide surface faces the front surface and the back surface of the semiconductor stacked unit among the inner peripheral surfaces of the recesses. It is preferable that it is formed in the portion to be (Claim 2).

In this case, the semiconductor stacked unit can be effectively supported by the pair of recesses.
In particular, according to the pair of recesses whose openings face each other, both ends in the longitudinal direction of the semiconductor multilayer unit can be supported with high reliability.

The guide unit includes a pair of guide portions each formed with the respective recesses, and a plate portion including a contact portion that contacts an end surface in the stacking direction of the semiconductor stacked unit. The guide portion is preferably fixed to the plate portion.
In this case, the position in the insertion direction of the semiconductor multi-layer unit with respect to the recess can be reliably regulated by contact with the plate portion.
The plate portion and the semiconductor laminated unit may be in contact with each other, but may be joined together.

Moreover, it is preferable that the said plate part forms a pair of refrigerant | coolant flow path connected to a pair of said header part (Claim 4).
In this case, it is possible to efficiently form a path for circulating the refrigerant through the semiconductor stacked unit by using the pair of refrigerant flow paths formed in the plate portion.

Moreover, it is preferable that the said plate part is a structural member which comprises a part of housing | casing of the said power converter device (Claim 5).
In this case, the semiconductor stacked unit can be held with high certainty in the power conversion device.

Further, it is preferable that the bottom surface of the concave portion is opposed to the semiconductor multilayer unit with a predetermined interval in the longitudinal direction (Claim 6).
In this case, the semiconductor stacked unit can be supported also in the longitudinal direction.

Further, it is preferable that the predetermined gap in the longitudinal direction between the semiconductor stacked unit and the guide unit is set wider than the gap in the predetermined width direction.
In this case, generally, a dimensional change due to thermal expansion that is larger in the longitudinal direction than in the width direction can be allowed.

Moreover, it is preferable that the said guide unit has a pressurization part which applies the load of a lamination direction with respect to the said semiconductor lamination unit (Claim 8).
In this case, a load in the stacking direction can be applied to the semiconductor stacked unit.
In the semiconductor stacked unit in which the contact load is applied in the stacking direction, the contact state between the semiconductor module and the cooling tube can be reliably maintained and the cooling performance of the semiconductor module can be improved.
Furthermore, in the semiconductor laminated unit laminated with the load in the lamination direction applied, the structural strength of the unit itself can be improved.

Moreover, each said header part is comprised with the bellows pipe, and it is preferable that the predetermined space | interval of the said width direction shall be 0.5 mm or more and 5 mm or less.
In this case, the durability of the semiconductor multi-layer unit can be improved while maintaining good assembly to the guide unit with respect to the semiconductor multi-layer unit having a header portion made of a tubular bellows pipe.

When the predetermined gap in the width direction is less than 0.5 mm, the assembling property of the semiconductor laminated unit with respect to the guide unit becomes poor.
On the other hand, if the predetermined gap in the width direction exceeds 5 mm, the semiconductor laminated unit may not be sufficiently supported by the guide unit.

Further, it is preferable that the guide unit holds a control board electrically connected to a control terminal which is an external terminal of the semiconductor module.
In this case, the semiconductor module can be controlled with high reliability by using the control board fixed to the guide unit.
Furthermore, by integrating the control board with the power conversion device, the entire device can be made compact.

Preferably, the guide unit holds a power bus bar electrically connected to a power terminal which is an external terminal of the semiconductor module.
In this case, the power signal controlled by the semiconductor module can be efficiently output via the power bus bar fixed to the guide unit.
In particular, according to the power bus bar fixed to the guide unit, it is possible to suppress the possibility of troubles such as electrical leaks and short circuits.
Furthermore, by integrating the power bus bar with the power conversion device, the entire device can be made compact.

The power conversion circuit is a circuit including a DC-DC converter circuit and an inverter circuit, and the semiconductor module is a power semiconductor module that constitutes the DC-DC converter circuit and the inverter circuit. (Claim 12).
In this case, since the amount of heat generated from the semiconductor element is large in the power semiconductor module constituting the power conversion circuit, the effect of the present invention is particularly effective.

Example 1
The power converter device 1 of this example is demonstrated using FIGS.
As shown in FIGS. 1 and 2, the power conversion device 1 is a device that includes a semiconductor module 10 that forms a power conversion circuit and a cooling tube 20 that forms a flow path of a refrigerant that cools the semiconductor module 10. .
The power conversion device 1 includes a semiconductor stacked unit 2 and a guide unit 50.
As shown in FIG. 2, the semiconductor laminated unit 2 is formed by alternately laminating cooling tubes 20 and semiconductor modules 10 each having a flat shape, and both ends of the cooling tubes 20 are connected to the refrigerant supply side and the discharge side. This is a unit communicating with a pair of header portions 41 and 42 constituting the.
As shown in FIGS. 6 and 7, the guide unit 50 faces the front surface 201 and the back surface 202 formed by the side edges along the longitudinal direction of the cooling tubes 20 in the semiconductor laminated unit 2 and has a predetermined width direction. It is a unit formed by forming a pair of guide surfaces 531 arranged with a gap therebetween.
This content will be described in detail below.

The power conversion apparatus 1 of this example is an apparatus for generating a drive current for energizing a travel motor for an electric vehicle, for example.
As shown in FIGS. 1 and 8, the power conversion device 1 includes a control board 110 that inputs a control signal to the semiconductor module 10, a capacitor and a reactor (not shown), in addition to the semiconductor stacked unit 2 and the guide unit 50. And a power circuit configured.

As shown in FIG. 2, the semiconductor laminated unit 2 is a unit having a multilayer laminated structure in which a plurality of semiconductor modules 10 and flat cooling tubes 20 are alternately laminated.
In the semiconductor laminated unit 2 of this example, two semiconductor modules 10 are arranged in parallel between adjacent cooling tubes 20.

As shown in FIGS. 3 and 4, the semiconductor module 10 includes a pair of IGBT elements 11 that are power semiconductor elements and a flywheel diode element 12 that is necessary for smoothing the rotation of the motor. This is a module disposed between the electrode heat sinks 15.
The semiconductor module 10 is formed by integrally molding the pair of electrode heat dissipation plates 15 and the elements 11 and 12 with a mold resin.
As shown in FIG. 4, the semiconductor module 10 is formed by resin molding so that the electrode heat dissipation plate 15 is exposed on both surfaces, and the exposed electrode heat dissipation plate 15 functions as a heat dissipation surface.

As shown in FIG. 3, the semiconductor module 10 is a power signal terminal as an external terminal, which is a power terminal 150 formed integrally with the electrode heat sink 15 and a control signal terminal. And a control terminal 160 held in the mold resin. The power terminal 150 and the control terminal 160 are disposed to face each other in a plane parallel to the electrode heat radiating plate 15.
Therefore, in the semiconductor laminated unit 2 using the semiconductor module 10, as shown in FIG. 6, the power terminal 150 protrudes on the front surface 201 side of the semiconductor laminated unit 2 and the control terminal 160 protrudes on the back surface 202 side. Can do.

As shown in FIG. 2, the cooling tube 20 of the present example is a flat tube 20 having a hollow portion (not shown) through which a refrigerant flows.
The cooling tube 20 is formed by perforating through holes (not shown) for connecting the bellows pipe 400 to flat surfaces of flat portions near both ends thereof. A sealing cap member 203 is joined to both ends of the cooling tube 20.

As shown in FIG. 2, the semiconductor multi-layer unit 2 includes a header part 41 for supply and a header part 42 for discharge as the header part. In this example, the header portions 41 and 42 are constituted by the bellows pipe 400 made of an aluminum material that can be expanded and contracted in the length direction.
The bellows pipe 400 is disposed in the gap between the adjacent cooling tubes 20, and is joined so that the through holes drilled in the cooling tubes 20 communicate with each other. And the some bellows pipe 400 arrange | positioned in each gap | interval of the laminated | stacked cooling tube 20 is comprised so that the said each header parts 41 and 42 may be formed as a whole.

Here, when the semiconductor module 10 is disposed between the cooling tubes 20, the semiconductor module 10 is disposed between the cooling tubes 20 with the bellows pipes 411 and 421 of the header portions 41 and 42 extended. After the arrangement, the cooling tube 20 and the semiconductor module 10 are brought into close contact with each other by shrinking the bellows pipe 400.
In order to electrically insulate the cooling tube 20 and the semiconductor module 10, a highly electrically insulating ceramic plate (not shown) is provided between the cooling tube 20 and the electrode heat dissipation plate 15 of the semiconductor module 10. ) Is arranged.

Further, as shown in FIGS. 5 and 6, the guide unit 50 of this example is a unit including a pair of guide portions 53 on which the guide surface 531 is formed and a plate portion 51 that fixes the pair of guide portions 53. is there.
As shown in FIG. 6, each guide portion 53 has a recess 530 having a groove shape along the stacking direction of the semiconductor stacked unit 2. Of the inner peripheral surface of the recess 530, two side wall surfaces facing each other are configured to form the guide surface 531.

A flange 535 for fixing to the plate portion is formed on one end face in the longitudinal direction of the concave portion 530 in the guide portion 53. The guide portion 53 is fixed in an upright state with respect to the plate portion 51 by bolting the flange 535 to the plate portion 51.
In the present example, the guide portion 53 and the plate portion 51 are configured as separate parts. However, instead of this, both may be configured as an integral structure.

As shown in FIG. 6, the pair of guide portions 53 are fixed to the plate portion 51 so as to face the openings of the respective concave portions 530.
The semiconductor laminated unit 2 is assembled to the guide unit 50 with one end surface in the laminating direction being in contact with the plate portion 51 and the both end portions in the longitudinal direction being accommodated in the concave portions 530. is there.

  As shown in FIG. 7, the guide unit 50 supports the front surface 201 and the back surface 202 of the semiconductor multilayer unit 2 by the pair of guide surfaces 531, and the length of the semiconductor multilayer unit 2 by the bottom surface 532 of the recess 530. It is comprised so that the end surface of a direction may be supported.

Each guide surface 531 is configured to face the front surface 201 or the back surface 202 of the semiconductor multilayer unit 2 with a gap a in a predetermined width direction. The bottom surface 532 is configured to face the end surface in the longitudinal direction of the semiconductor multilayer unit 2 with a predetermined longitudinal gap b.
Here, in the guide unit 50 of the present example, in consideration of the fact that the dimensional change due to thermal expansion occurring in the semiconductor laminated unit becomes large in the longitudinal direction, the size relationship between the gaps is a <b.

Furthermore, in the power converter 1 of this example, as shown in FIG. 1, the plate portion 51 is configured so as to form a part of the casing of the power converter 1.
The plate portion 51 is formed with coolant channels 511 and 512 communicating with the pair of header portions 41 and 42. When the semiconductor laminated unit 2 is assembled to the guide unit 50, the coolant channels 511, 512 communicates with the header portions 41 and 42.

The surface of the plate portion 51 to which the semiconductor multilayer unit 2 is fixed is configured to fix components such as a capacitor and a reactor (not shown) in addition to the semiconductor multilayer unit 2.
A joint portion for connecting an external pipe to each of the refrigerant flow paths 511 and 512 is joined to a surface forming the outer surface of the power conversion device 1 in the plate portion 51.

Furthermore, as shown in FIG. 5, the guide unit 50 of this example includes a pinching plate 52 that generates a load that pressurizes the semiconductor multilayer unit 2 in the stacking direction.
The pinching plate 52 is configured to sandwich the semiconductor multilayer unit 2 with a load in the stacking direction acting between the plate portion 51.
In this example, the end surface in the stacking direction of the semiconductor stacked unit 2 is bonded to the plate portion 51.

The pinching plate 52 is configured to couple the pair of guide portions 53 in a bridge shape by bolting to the longitudinal end surfaces of the respective guide portions 53.
The clamping plate 52 is formed by drilling bolt holes for inserting fixing bolts at both ends, and abutting against the end surface in the stacking direction of the semiconductor stacking unit 2 between the two bolt holes. A contact portion 520 is provided.

As shown in FIG. 5, the contact portion 520 is formed to be thicker than both end portions in the longitudinal direction, and forms a pressing surface that protrudes toward the semiconductor multilayer unit 2 when attached to the guide portion 53. It is comprised so that it may do.
The clamping plate 52 is configured to apply a load corresponding to the bolt tightening torque when the bolt is coupled to the end face of the guide portion 53 from the contact portion 520 toward the semiconductor multilayer unit 2. It is.

Therefore, in the power conversion device 1 of this example, by applying an appropriate contact load between the cooling tube 20 and the semiconductor module 10, an appropriate contact load is applied between the two, A wide contact area can be secured.
Therefore, in the semiconductor laminated unit 2 of this example, the movement of heat between the semiconductor module 10 and the cooling tube 20 is promoted, and the semiconductor module 10 can be efficiently cooled.
In particular, in the power conversion device 2 of this example, since the cooling tubes 20 are in contact with both sides of the semiconductor module 10, the performance of cooling the semiconductor module 10 is very high.

As described above, in the electrode conversion apparatus 1 of this example, as shown in FIG. 8, the power terminal 150 of the semiconductor module 10 protrudes to the front surface 201 side of the semiconductor cooling unit 2, and the control terminal 160 extends to the rear surface 202 side. It is configured to protrude.
Therefore, in this power converter 1, as shown in the figure, the power bus bar 155 for connecting the power terminals 150 of the respective semiconductor modules 10 is arranged on the surface 201 side of the semiconductor laminated unit 2, thereby providing a power signal. Efficient wire handling is possible.

  In the power conversion device 1 of this example, as shown in the figure, the power bus bar 155 can be fixed reliably and easily using the pair of guide portions 53. That is, if the power bus bar 155 is attached in a bridge shape using the attachment portions formed on the side surfaces of the pair of guide portions 53, the power bus bar 155 is arranged with a certain gap from the surface 201 of the semiconductor stacked unit 2. be able to.

Similarly, in the power conversion device 1, as shown in FIG. 8, by arranging the control board 165 electrically connected to the control terminal 160 of each semiconductor module 10 on the back surface 202 side of the semiconductor multilayer unit 2, The signal line between the control board 165 and the control terminal 160 can be shortened or omitted.
In the power conversion device 1 of this example, the control board 155 can be fixed reliably and easily using the pair of guide portions 53.

(Example 2)
This example is an example in which the structure of the clamping plate is changed based on the power conversion device of the first embodiment. This example will be described with reference to FIG.
The guide unit 50 of this example is configured to apply a load in the stacking direction to the semiconductor stacked unit 2 using a spring member 55 configured to be elastically deformable.

The pair of guide portions 53 of this example is formed higher than the stacking height of the semiconductor stacked unit 2. Further, engaging pins 538 for engaging both end portions of the spring member 55 are arranged at portions of the guide portions 53 protruding from the semiconductor laminated unit 2.
When both ends of the spring member 55 are engaged with the engaging pins 538 of the respective guide portions 53, the intermediate portion is bent toward the semiconductor laminated unit 2 and presses the semiconductor laminated unit 2. It is configured.

Further, a flat pressing plate 550 is arranged between the spring member 55 and the end face of the semiconductor laminated unit 2.
The spring member 55 of this example is configured to act on the end surface of the semiconductor multilayer unit 2 with high uniformity of the elastic force through the pressing plate 550.

The perspective view which shows a part of power converter device in Example 1. FIG. FIG. 3 is a front view showing a semiconductor stacked unit in the first embodiment. FIG. 3 is a top view illustrating the semiconductor module according to the first embodiment. Sectional drawing which shows the cross-section of the semiconductor module in Example 1 (AA arrow sectional drawing in FIG. 3). The front view which shows the assembly | attachment state of the semiconductor lamination | stacking unit in Example 1. FIG. FIG. 3 is a top view illustrating an assembled state of the semiconductor stacked unit in the first embodiment. The enlarged view which shows the assembly | attachment state of the semiconductor lamination | stacking unit in Example 1. FIG. FIG. 3 is a top view showing a wiring state of a semiconductor multilayer unit in Example 1. The front view which shows the assembly | attachment state of the semiconductor lamination | stacking unit in Example 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Power converter 10 Semiconductor module 11 IGBT element 12 Flywheel diode element 2 Semiconductor laminated unit 20 Cooling tube 30 Insulating member 41, 42 Header part 400 Bellows pipe 50 Guide unit 53 Guide part 531 Guide surface

Claims (12)

In a power conversion device having a semiconductor module constituting a power conversion circuit and a cooling tube that forms a flow path of a refrigerant for cooling the semiconductor module,
A semiconductor formed by alternately laminating the cooling tube having a flat shape and the flat semiconductor module, and connecting both ends of each cooling tube to a pair of header portions for supplying and discharging the refrigerant. A laminated unit;
A guide unit formed with a pair of guide surfaces arranged with a gap in a predetermined width direction facing a front surface and a back surface formed by side edges along the longitudinal direction of each of the cooling tubes in the semiconductor stacked unit; A power converter characterized by comprising.   In claim 1, the guide unit has a groove shape formed along the stacking direction of the semiconductor stacked unit, and has a pair of recesses arranged so that the opening faces each other, The semiconductor multilayer unit is arranged in a state where both end portions in the longitudinal direction are accommodated in the respective recesses, and the guide surface includes the surface of the semiconductor stack unit and the surface of the inner peripheral surface of the recess. It is formed in the part which faces a back surface, The power converter device characterized by the above-mentioned.   3. The guide unit according to claim 2, wherein the guide unit includes a pair of guide portions each formed with the recesses, and a plate portion including a contact portion that contacts the end surface of the semiconductor stacked unit in the stacking direction. The pair of guide portions is fixed to the plate portion.   4. The power conversion device according to claim 3, wherein the plate portion forms a pair of refrigerant flow paths communicating with the pair of header portions.   5. The power conversion device according to claim 2, wherein the plate portion is a structural member constituting a part of a casing of the power conversion device.   6. The power conversion device according to claim 2, wherein the bottom surface of the concave portion faces the semiconductor laminated unit with a predetermined interval in the longitudinal direction.   7. The power conversion device according to claim 6, wherein the predetermined gap in the longitudinal direction between the semiconductor multilayer unit and the guide unit is set wider than the gap in the predetermined width direction.   8. The power conversion device according to claim 1, wherein the guide unit includes a pressurizing unit that applies a load in a stacking direction to the semiconductor stacked unit. 9.   9. The power conversion according to claim 1, wherein each of the header portions is configured by a bellows pipe, and the predetermined interval in the width direction is 0.5 mm or more and 5 mm or less. apparatus.   10. The power conversion device according to claim 1, wherein the guide unit holds a control board that is electrically connected to a control terminal that is an external terminal of the semiconductor module. 11.   11. The power conversion device according to claim 1, wherein the guide unit holds a power bus bar electrically connected to a power terminal that is an external terminal of the semiconductor module.   12. The power conversion circuit according to claim 1, wherein the power conversion circuit includes a DC-DC converter circuit and an inverter circuit, and the semiconductor module includes the DC-DC converter circuit and the inverter circuit. A power conversion device comprising a power semiconductor module.

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