JP4450632B2 - Power converter - Google Patents

Description

  The present invention relates to a power converter, and more particularly, to a power converter provided with a resin cooling jacket.

In a conventional power converter, a power semiconductor element is mounted on a metal heat sink, and the back surface of the heat sink is further cooled by cooling water (for example, Patent Document 1).
JP 2001-308246 A

  In such a structure, the cooling effect of the power semiconductor element by the cooling water is reduced by the thermal resistance of the heat sink. In other words, it is necessary to suppress the amount of heat generated by the power semiconductor element by the amount that the cooling effect is reduced by the heat resistance of the heat sink. As a result, there is a problem that the amount of current supplied to the power semiconductor element is limited, and the capability of the power semiconductor element cannot be fully utilized.

  Therefore, an object of the present invention is to provide a power conversion device that improves the cooling efficiency of the power semiconductor element and fully utilizes the capability of the power semiconductor element.

The present invention includes a cooling jacket formed of a resin and provided with a recess, and a semiconductor module having a heat dissipation surface, the semiconductor module being placed on the cooling jacket and covering the recess with the heat dissipation surface. The area surrounded by the surface is used as a cooling water flow path, and the cooling jacket is provided with an insert-formed wiring conductor, and the wiring conductor has one end connected to the external terminal of the semiconductor module and the other end of the cooling jacket. The power conversion device is characterized by being exposed to the outside.

  In the power converter according to the present invention, the cooling efficiency of the power semiconductor element is improved, and the characteristics of the power semiconductor element can be fully utilized.

  In addition, by using a resin cooling jacket, the power conversion device can be reduced in size and weight, and the cost can be reduced.

Embodiment 1 FIG.
FIG. 1 is a top view of a power conversion device denoted as a whole by 100 according to the present embodiment. 2 is a cross-sectional view of FIG. 1 when viewed in the II direction.

  As shown in FIG. 1, the power conversion device 100 includes three semiconductor modules 1 and a cooling jacket 2. Each semiconductor module 1 has three terminals 32, 33 and 34. The cooling jacket 2 is made of an injection molded product of a synthetic resin such as PPS (Polyphenylene Sulfide) or PBT (polybutylene terephthalate). In the cooling jacket 2, wiring conductors 40 to 44 are integrally formed. A part of each of the wiring conductors 40 to 44 is exposed on the surface of the cooling jacket 2.

As shown in the sectional view of FIG. 2, the semiconductor module 1 includes an insulating substrate 11 such as Al ₂ O ₃ . A metal foil 12 made of copper or the like is provided on the back surface of the insulating substrate 11. On the other hand, a heat spreader 13 such as copper is provided on the surface of the insulating substrate 11, and a semiconductor element 14 such as IGBT is mounted thereon. The semiconductor element 14 and the like are sealed with a sealing resin 15 such as an epoxy resin.

  The semiconductor module 1 is fixed on the cooling jacket 2 with a seal member 3 such as an O-ring interposed therebetween. Thereby, the flow path 21 for circulating the cooling water is formed, and the back surface of the semiconductor module 1 forms one surface of the flow path 21. Since the insulating substrate 11 provided with the metal foil 12 is in direct contact with the cooling water, the cooling efficiency of the semiconductor element 14 is improved as compared with the case where the insulating substrate 11 is cooled through a heat sink having a certain thermal resistance as in the prior art. . As a result, the upper limit of the amount of current that can be supplied to the semiconductor element 14 is increased, and the characteristics of the semiconductor element 14 can be fully utilized.

  As described above, the wiring conductor 40 is embedded in the cooling jacket 2. A part of the wiring conductor 40 becomes a connection terminal 40a and is connected to the terminal 12 of the semiconductor module by, for example, a bolt. Further, a part of the wiring conductor 40 becomes an external terminal 40b, and a DC power source such as a battery and a motor (not shown) are connected thereto.

  Thus, the power converter device 100 concerning this Embodiment has the structure where the semiconductor module 1 is directly cooled with cooling water. For this reason, the thermal resistance of the material forming the cooling jacket 2 does not affect the cooling of the semiconductor module 1, and the cooling jacket 2 can be manufactured using resin.

  Thus, by using resin as the material of the cooling jacket 2, the wiring conductors 40 to 44 can be sealed and integrally formed in the cooling jacket 2, and the number of parts and the assembly process can be reduced. Moreover, the freedom degree of the shape design of the flow path 21 becomes large. Furthermore, the power converter 100 can be reduced in weight.

Embodiment 2. FIG.
FIG. 3 is a cross-sectional view of the power conversion device denoted as a whole by 200 according to the present embodiment, and is a cross-sectional view when viewed in the same direction as the II direction of FIG. 3, the same reference numerals as those in FIG. 2 denote the same or corresponding parts.

In the power converter 200, the cooling jacket 2 extends upward so as to surround the periphery of the semiconductor module 1, and forms a wall 2a. The upper end of the wall 2a is covered with a cover 7 made of, for example, an epoxy resin to form a housing. A smoothing capacitor 5 and a control board 6 for controlling the semiconductor module 1 are housed in the housing. The smoothing capacitor 5 and the control board 6 are fixed by appropriate fixing means (not shown).
In addition, the inside of a housing | casing can be waterproofed by arrange | positioning a sealing material (not shown) between the wall part 2a and the cover 7. FIG.

  In the power conversion device 200 according to the present embodiment, the smoothing capacitor 5 and the control board 6 are provided in a case integrally formed with the cooling jacket, and therefore it is not necessary to provide a separate case. Furthermore, since the semiconductor module 1, the smoothing capacitor 5, and the control board 6 are connected in the same housing, only the external terminal 40 b is exposed to the outside of the power conversion device 200. Terminals can be waterproofed easily.

Embodiment 3 FIG.
FIG. 4 is a cross-sectional view of the power conversion device represented as a whole by 300 according to the present embodiment, and is a cross-sectional view when viewed in the same direction as the II direction of FIG. 4, the same reference numerals as those in FIG. 2 denote the same or corresponding parts.

  In the power conversion device 300, similarly to the power conversion device 200 described above, the cooling jacket 2 extends upward so as to surround the periphery of the semiconductor module 1, and a housing is formed. A smoothing capacitor and a control board 6 are accommodated in the housing and fixed by appropriate fixing means (not shown).

  Further, the pressing member 8 is disposed on the semiconductor module 1, and the pressing member 8 is fixed in a state where the pressing member 8 presses the semiconductor module 1 against the cooling jacket 2. Preferably, the three semiconductor modules 1 shown in FIG. 1 are pressed by one pressing member 8 and fixed. Thereby, the number of parts of fixing means, such as a nut, can be reduced.

  For the pressing member 8, for example, a high-strength metal plate such as stainless steel is used, and the electromagnetic wave emitted from the semiconductor module 1 is also shielded.

  Further, the pressing member 8 includes a bent portion 8a, and ensures high bending rigidity even if the pressing member 8 is thin. It is preferable that the bending part 8a is provided in the part to which a stress is applied locally like the vicinity of the hole which lets the nut fixed to the cooling jacket 2 pass, for example.

  Further, when the three semiconductor modules 1 are pressed by one pressing member 8, the pressing member 8 may have a structure having a slit along one side of the semiconductor module at a position between the semiconductor modules. By having such a slit, the pressing member 8 is partially apt to be distorted, and variations in the pressing force of the pressing member 8 due to differences in the thickness of the semiconductor module can be reduced.

Embodiment 4 FIG.
FIG. 5 is a cross-sectional view of the power conversion device denoted as a whole by 400 according to the present embodiment, and is a cross-sectional view when viewed in the same direction as the II direction of FIG. 1. 5, the same reference numerals as those in FIG. 2 indicate the same or corresponding parts.

  In the power conversion device 400, in addition to the power conversion device 300 described above, a base is provided on the bottom surface of the flow path 21 provided in the cooling jacket 2. A plate-like partition plate 24 that spreads from the upper surface of the table part is placed on the table part. The flow path 21 is divided into an inlet-side header flow path 21 a, an outlet-side header flow path 21 b, and a cooling flow path 27 by a partition plate 24. That is, the inlet-side header channel 21 a and the outlet-side header channel 21 b provided substantially in parallel are connected by the cooling channel 27.

  The cooling water that has entered the inlet-side header flow path 21a flows along the one end of the partition plate 24 in a direction perpendicular to the paper surface of FIG. The cooling flow path 27 is provided below each semiconductor module 1, and connects the inlet side header flow path 21a and the outlet side header flow path 21b. For this reason, the cooling water passing through the inlet-side header flow path 21a passes through the cooling flow path 27, cools the semiconductor module 1, and then enters the outlet-side header flow path 21b and is discharged.

  In addition, the pressure loss from the inlet side header flow path 21a to the outlet side header flow path 21b via the cooling flow path 27 is more than the pressure loss in the inlet side header flow path 21a and the outlet side header flow path 21b. It is preferably 3 times larger. Thereby, the flow velocity distribution in the cooling flow path 27 can be reduced. Further, as in the present embodiment, when a plurality of (here, three) cooling channels 27 are arranged in parallel between the inlet-side header channel 21a and the outlet-side header channel 21b, The flow velocity distribution between the cooling flow paths 27 can also be reduced.

Embodiment 5 FIG.
FIG. 6 is a cross-sectional view of the power conversion device denoted as a whole by 500 according to the present embodiment, and is a cross-sectional view when viewed in the same direction as the II direction of FIG. In FIG. 6, the same reference numerals as those in FIG. 2 denote the same or corresponding parts.

  In the power conversion device 500, in addition to the power conversion device 400 described above, a plurality of protrusions 28 are provided on the upper surface of the partition plate 24. The protrusion 28 may have a shape such as a quadrangular prism or a cylinder, or may have a stripe shape extending in a direction perpendicular to the paper surface of FIG.

  Thus, by providing the protrusions 28 in the cooling flow path 27, turbulent flow is likely to occur in the cooling water flowing through the cooling flow path 27, and the cooling efficiency of the semiconductor module 1 is improved.

Embodiment 6 FIG.
FIG. 7 is a cross-sectional view of the power conversion apparatus denoted as a whole by 600 according to the present embodiment, and is a cross-sectional view when viewed in the same direction as the II direction of FIG. In FIG. 7, the same reference numerals as those in FIG. 2 denote the same or corresponding parts.

  In the power conversion device 600, in addition to the above-described power conversion device 500, an opening is also provided at the bottom of the flow path 21, and the opening is closed with a seal plate 9 made of a metal having a high heat transfer coefficient. In the power converter 600, the smoothing capacitor 5 disposed in the housing is placed so as to contact the seal plate 9. Thereby, the smoothing capacitor 5 is cooled. The electrode 51 of the smoothing capacitor 5 is connected to the wiring conductor 40.

  The wall portion 23 of the cooling jacket 2 is also provided on the bottom side of the cooling jacket 2, that is, around the smoothing capacitor 5, and a cover 7 is attached to the end of the wall portion 23 via a seal member (not shown). Yes. With this structure, the smoothing capacitor 5 is protected and waterproofed.

  Such a structure may be applied to the power conversion devices 300 and 400 shown in FIGS.

  In addition, although Embodiment 1-6 demonstrated the power converter device which converts direct current into three-phase alternating current, this invention is not limited to this structure, The semiconductor module which requires cooling was used. The present invention can also be applied to other power conversion device structures.

  Moreover, although the case where the three semiconductor modules 1 were included was described in Embodiment 1-6, this invention is applicable also when it has the semiconductor modules 1 other than three.

It is a top view of the power converter device concerning Embodiment 1 of the present invention. It is sectional drawing of the power converter device concerning Embodiment 1 of this invention. It is sectional drawing of the power converter device concerning Embodiment 2 of this invention. It is sectional drawing of the power converter device concerning Embodiment 3 of this invention. It is sectional drawing of the power converter device concerning Embodiment 4 of this invention. It is sectional drawing of the power converter device concerning Embodiment 5 of this invention. It is sectional drawing of the power converter device concerning Embodiment 6 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Semiconductor module, 2 Cooling jacket, 3 Seal member, 11 Insulating board, 12 Metal foil, 13 Heat spreader, 14 Semiconductor element, 15 Sealing resin, 21 Flow path, 32 terminal, 40 Wiring conductor, 40a Connection terminal, 40b Outside Terminal, 100 Power converter.

Claims (5)

A cooling jacket molded from resin and provided with a recess;
A semiconductor module having a heat dissipating surface, the semiconductor module being placed on the cooling jacket and covering the recess with the heat dissipating surface,
A region surrounded by the recess and the heat radiating surface is a cooling water flow path,
The cooling jacket includes an insert-formed wiring conductor;
One end of the wiring conductor is connected to an external terminal of the semiconductor module, and the other end is exposed to the outside of the cooling jacket . The cooling jacket has a base protruding from the bottom of the recess;
A plate-like partition plate that spreads outward from the upper surface of the base part is placed on the base part,
The flow path is provided substantially in parallel with the base portion interposed therebetween, and the inlet-side header flow path and the outlet-side header flow path positioned below the partition plate, and the inlet-side header flow path above the partition plate The power conversion device according to claim 1, further comprising a cooling flow path that connects the path and the outlet-side header flow path. The pressure loss from the inlet-side header channel to the outlet-side header channel via the cooling channel is three times the pressure loss in the inlet-side header channel and the outlet-side header channel The power converter according to claim 2 , wherein the power converter is larger than the above. The power converter according to claim 2 or 3 , wherein the partition plate has a protrusion on the surface that protrudes into the cooling channel. The cooling jacket has a base protruding from the bottom of the recess;
An inlet-side header channel and an outlet-side header channel provided substantially parallel to each other across the platform, and the inlet-side header channel and the outlet-side header channel on the platform A cooling flow path connecting the
The power converter according to claim 1, further comprising an opening provided on a bottom surface of the recess, the opening being closed by a metal plate on which a capacitor is placed.

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