WO2013145508A1 - Power conversion apparatus - Google Patents

Abstract

Provided is a power conversion apparatus, which is made compact as a whole, while eliminating insufficiency of insulating distance. A power conversion apparatus (1) is provided with: a semiconductor power module (11) having one surface thereof bonded to a cooling body (3); a plurality of mounting substrates (22, 23), each of which has mounted thereon circuit components including a heat generating circuit component that drives the semiconductor power module; heat transmitting supporting members (32, 33), which transmit heat of the mounting substrates to the cooling body; and an insulation ensuring region (43), which is formed in an insulating distance insufficient region where the insulating distance is insufficient between the mounting substrates.

Description

Power converter

The present invention supports a plurality of mounting boards on which a circuit component including a heat generating circuit component for driving the semiconductor switching element is mounted at a distance on a semiconductor power module incorporating a semiconductor switching element for power conversion. The present invention relates to a power converter.

As this type of power conversion device, as shown in Patent Document 1, a mounting board on which a heat generating circuit component is mounted is connected to a cooling body via a housing, and heat generated by the mounting board is radiated to the cooling body. A power conversion device having a configuration is known.
In the power conversion device described in Patent Document 1, a semiconductor power module 101 including a semiconductor switching element for power conversion is disposed on a cooling body 100 as shown in FIG. On the upper surface side of the semiconductor power module 101, a mounting substrate 102 is supported by a heat transfer support member 106 connected to a housing 105 via a heat transfer material 104 provided on the bottom surface. By doing in this way, since the heat generated by the mounting substrate 102 can be dissipated through the path of the heat transfer material 104 → the heat transfer support member 106 → the housing 105 → the cooling body 100, the mounting substrate can be cooled. Reference numeral 107 denotes a capacitor disposed at the bottom of the housing 105. Reference numeral 108 denotes an auxiliary machine inverter installed at the bottom of the cooling body.

Japanese Patent No. 4657329

By the way, in the conventional example described in Patent Document 1, the heat generated in the control circuit board is radiated through the path of the control circuit board → the heat radiating member → the metal base plate → the housing → the water cooling jacket. Yes. For this reason, when the housing is used as a part of the heat transfer path, the housing is also required to have good heat transfer properties, and the material is limited to a metal having high thermal conductivity, which is reduced in size and weight. However, there is an unsolved problem that it is difficult to select a lightweight material such as a resin and it is difficult to reduce the weight.

Also, since the housing is often required to be waterproof and dustproof, apply a liquid sealant or sandwich rubber packing between the metal base plate and the housing and between the housing and the water cooling jacket. Etc. are generally performed. Liquid sealants and rubber packings generally have a low thermal conductivity, and there is an unsolved problem that the thermal resistance increases and the cooling efficiency decreases due to the presence of these in the thermal cooling path.

On the other hand, downsizing of power converters is required. When this compactness is performed, the heat generation density in the housing increases, and there is a high possibility that the durability of the electronic components that are mounted on the mounting board and perform the control as the temperature rises decreases. In order to prevent this, the apparatus can be made compact by adopting a structure that ensures cooling performance so that the temperature in the housing does not rise. However, there is a limit to improving the cooling capacity in the housing, and in order to achieve compactness, it is necessary to limit the height of the power converter. For this purpose, the distance between the mounting boards arranged in the housing becomes a problem.

Since circuit components with different heights are mounted between each mounting board, it is meaningless to determine the distance between the mounting boards without mounting the circuit parts. It is necessary to assume. At this time, if the distance between the mounting boards is set to the required insulation distance between the circuit component with the maximum height and the other mounting board facing it, there is no problem from the point of insulation. If there is a circuit component that does not have sufficient insulation distance even if there is a single distance between them, the distance will be determined according to this circuit component, and the distance between each mounting board will become longer, so Will also increase in size.

On the other hand, in order to secure an insulation distance, it is conceivable to install an insulating sheet on the opposite surface of the other mounting board facing the circuit component mounted on one mounting board. However, the insulation sheet has low heat conductivity, and it is difficult to transfer heat generated from the heat generating circuit components, and there is an unsolved problem that the heat generated by the heat generating circuit components is trapped between the mounting boards and the cooling capacity is lowered. is there.
Then, this invention is made paying attention to the unsolved subject of the said prior art example, and it aims at providing the power converter device which can make the whole compact, eliminating the lack of insulation distance.

In order to achieve the above object, a first aspect of a power conversion device according to the present invention includes a semiconductor power module in which one surface is joined to a cooling body and a circuit component including a heat generating circuit component that drives the semiconductor power module. Insulating insulation formed in an insulation distance shortage region where the insulation distance is insufficient between the plurality of mounting boards and the heat transfer support member by transferring the heat of the plurality of mounting boards to the cooling body and the plurality of mounting boards. And an area.

According to the first aspect, when an insulation distance shortage region in which the insulation distance is partially insufficient between a plurality of mounting substrates occurs, insulation is performed on the mounting substrate on which the circuit component facing the insulation distance shortage region is not mounted. A reserved area is formed. The insulation securing area is a part of a heat transfer support member that secures an insulation distance by partially attaching an insulating sheet to the mounting board facing the insufficient insulation area, or dissipates the heat generated by the heating circuit components to the cooling body. The insulating distance is secured by removing the insulating layer, or the insulating distance is secured by inserting an insulative heat transfer member between the circuit component that becomes the insufficient insulation region and the mounting substrate facing the circuit board.
As a result, even if the insulation distance between parts of the mounting circuit boards is insufficient, the insulation distance can be secured in the insufficient insulation securing area, and the entire configuration is made by making the distance between the mounting boards shorter than the required insulation distance. Can be made compact.

Moreover, the 2nd aspect of the power converter device which concerns on this invention makes the said insulation ensuring area | region the area | region which ensures insulation by inserting an insulating heat-transfer member in the position facing the said insulation distance shortage area | region. .
According to the second aspect, the insulating heat transfer member is interposed between the mounting substrate and the heat transfer support member, so that heat is dissipated while ensuring insulation between the mounting substrate and the heat transfer support member. The effect can be improved.

Moreover, the 3rd aspect of the power converter device which concerns on this invention makes the said insulation ensuring area | region the area | region which arrange | positions an insulating sheet in the position facing the said insulation distance insufficient area | region, and ensures insulation.
According to this third aspect, since the insulating sheet is disposed not only on the entire surface of the heat transfer support member but only at a position facing the insufficient insulation region, the heat transfer support members other than the insulating sheet are disposed facing each other. Exposed to heat generating circuit components. For this reason, it becomes possible to absorb the heat generated by the heat generating circuit component facing the heat transfer support member, and it is possible to reliably prevent heat from being generated between the mounting boards.

Moreover, the 4th aspect of the power converter device which concerns on this invention WHEREIN: The said insulation ensuring area | region is made into the area | region which removes the said heat-transfer support member of the position facing the said insulation distance insufficient area | region, and ensures insulation. .
According to the fourth aspect, it is possible to secure the insulation distance by removing the heat transfer support member facing the insulation distance shortage region. In this case, even if the heat transfer support member is removed, an insulating heat transfer member exists between the mounting substrate and a long insulation distance can be secured.

Further, according to a fifth aspect of the power conversion device of the present invention, the heat transfer support member includes a heat transfer support plate portion that supports the mounting substrate via the heat transfer member, and a side surface of the heat transfer support plate portion. And a heat transfer support side plate portion connected to the cooling body.
According to the fifth aspect, since the heat transfer support member is composed of the heat transfer support plate portion and the heat transfer support side plate portion, the heat transfer support plate portion is integrated with the mount substrate when the mounting substrate is assembled. The heat transfer support side plate portion can be connected to the cooling body, and finally the heat transfer support plate portion and the heat transfer support side plate portion can be connected to form a heat transfer support member.

Moreover, as for the 6th aspect of the power converter device which concerns on this invention, the said heat-transfer support plate part and the said heat-transfer support side plate part are integrally formed.
According to the sixth aspect, since the heat transfer support plate portion and the heat transfer support side plate portion are integrally formed, there is no seam between the two and the heat resistance can be kept low, and the heat dissipation effect is improved. Can do.
Moreover, as for the 7th aspect of the power converter device which concerns on this invention, the said heat-transfer member is comprised with the insulator which has insulation.
According to the seventh aspect, since the heat transfer member has insulation, insulation between the mounting substrate and the heat transfer support member can be reliably performed.

Moreover, the 8th aspect of the power converter device which concerns on this invention has fixed the said mounting substrate and the heat-transfer support plate part of the said heat-transfer support member with the clamping fixing member via the said heat-transfer member.
According to the eighth aspect, since the heat transfer member is fixed between the mounting substrate and the heat transfer support plate portion of the heat transfer support member by the fastening member, the assembly can be easily performed. .
Further, a ninth aspect of the power conversion device according to the present invention is an interval adjustment that maintains the interval between the mounting substrate and the heat transfer support plate portion of the heat transfer support member at a predetermined value around the tightening fixing member. A member is inserted.
According to the ninth aspect, when the heat transfer member is an elastic body, the compression rate of the heat transfer member can be accurately defined.

According to the present invention, even when an insulation distance shortage region in which the insulation distance is partially insufficient between the mounting boards is formed, insulation can be secured in the insulation secured region, and this insulation secured region is insufficient in the insulation distance. Since the heat transfer support member is exposed at a position facing the heat generating circuit component and the heat generation of the heat generating circuit component on the opposite surface side is not accumulated, the heat can be radiated to the cooling body. Therefore, the heat dissipation effect can be improved and the distance between the mounting boards can be made shorter than the required insulation distance, and the housing can be made compact.
In addition, since the casing does not require good heat conductivity, a lightweight material such as a resin can be used for the casing, and the casing can be reduced in weight and an inexpensive power conversion device can be provided.

It is sectional drawing which shows the whole structure of 1st Embodiment of the power converter device which concerns on this invention. It is a figure which shows the attachment method to the heat-transfer support member of a mounting board | substrate. It is sectional drawing which shows the state which attached the mounting board | substrate to the heat-transfer support member. Mounting board It is sectional drawing of the principal part which shows 2nd Embodiment of the power converter device which concerns on this invention. It is sectional drawing of the principal part which shows 3rd Embodiment of the power converter device which concerns on this invention. It is a bottom view which shows the notch state of the heat-transfer support plate part of 3rd Embodiment. It is sectional drawing which shows a prior art example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing the overall configuration of a power converter according to the present invention.
In the figure, reference numeral 1 denotes a power converter, and the power converter 1 is housed in a housing 2. The casing 2 is formed by molding a synthetic resin material, and includes a lower casing 2A and an upper casing 2B that are divided vertically with a cooling body 3 having a water-cooling jacket structure interposed therebetween.

The lower housing 2A is a bottomed rectangular tube. The lower casing 2A has an open upper portion covered with a cooling body 3, and a smoothing film capacitor 4 is accommodated therein.
The upper housing 2B includes a rectangular tube 2a having an open upper end and a lower end, and a lid 2b that closes the upper end of the rectangular tube 2a. The lower end of the rectangular tube 2a is closed by the cooling body 3. Although not shown, a sealing material such as application of a liquid sealant or sandwiching rubber packing is interposed between the lower end of the rectangular tube 2a and the cooling body 3.

The cooling body 3 has a cooling water supply port 3 a and a drain port 3 b opened to the outside of the housing 2. The water supply port 3a and the drainage port 3b are connected to a cooling water supply source (not shown) via, for example, a flexible hose. The cooling body 3 is integrally formed by casting aluminum or aluminum alloy having high thermal conductivity, such as die casting. And as for the cooling body 3, the lower surface is made into a flat surface, and the upper surface is formed with the square-frame-shaped peripheral groove 3d leaving the center part 3c.

The power conversion device 1 includes a semiconductor power module 11 including, for example, an insulated gate bipolar transistor (IGBT) as a semiconductor switching element that constitutes, for example, an inverter circuit for power conversion. The semiconductor power module 11 includes an IGBT in a flat rectangular parallelepiped insulating case body 12, and a metal heat dissipating member 13 is formed on the lower surface of the case body 12. The case body 12 and the heat radiating member 13 are formed with insertion holes 15 through which fixing screws 14 as fixing members are inserted at the four corners when viewed from above. In addition, on the upper surface of the case body 12, substrate fixing portions 16 having a predetermined height are formed to protrude at four locations inside the insertion hole 15.

A driving circuit board 21 on which a driving circuit for driving an IGBT built in the semiconductor power module 11 is mounted is fixed to the upper end of the board fixing portion 16. In addition, a control circuit including a heat generation circuit component having a relatively large heat generation amount or a high heat generation density for controlling the IGBT built in the semiconductor power module 11 with a predetermined interval above the drive circuit board 21 is mounted. A control circuit board 22 as a mounting board is fixed. Further, a power supply circuit board 23 as a mounting board on which a power supply circuit including a heating circuit component for supplying power to the IGBT built in the semiconductor power module 11 is mounted at a predetermined interval above the control circuit board 22 is fixed. ing.

Then, the drive circuit board 21 is inserted into the insertion hole 21 a formed at a position facing the board fixing part 16, and the male screw part 24 a of the joint screw 24 is inserted, and the male screw part 24 a is formed on the upper surface of the board fixing part 16. It is fixed by screwing into the part 16a.
Further, the control circuit board 22 inserts the male screw portion 25 a of the joint screw 25 into an insertion hole 22 a formed at a position facing the female screw portion 24 b formed at the upper end of the joint screw 24, and this male screw portion 25 a is inserted into the joint screw 24. It is fixed by screwing into the female screw portion 24b.

Further, the power supply circuit board 23 inserts a fixing screw 26 into an insertion hole 23 a formed at a position facing the female screw portion 25 a formed at the upper end of the joint screw 25, and this fixing screw 26 is inserted into the female screw portion 25 a of the joint screw 25. It is fixed by screwing.
In addition, the control circuit board 22 and the power circuit board 23 are uniquely formed with a heat dissipation path to the cooling body 3 by the heat transfer support members 32 and 33 without passing through the housing 2. These heat transfer support members 32 and 33 are formed of a metal having a high thermal conductivity, such as aluminum or an aluminum alloy.

Also, the heat transfer support members 32 and 33 have a square frame-shaped common bottom plate portion 34 that is disposed in the circumferential groove 3d of the cooling body 3 that supports the control circuit board 22 and serves as a cooling body contact plate portion. Therefore, the heat transfer support members 32 and 33 are integrally connected by the bottom plate portion 34. And the heat-transfer support members 32 and 33 and the baseplate part 34 have a black surface. In order to blacken the surfaces of the heat transfer support members 32 and 33 and the bottom plate portion 34, the surface may be coated with a black resin or painted with a black paint.

Thus, by making the surfaces of the heat transfer support members 32 and 33 and the bottom plate portion black, the heat emissivity becomes larger than the metal material color, and the amount of radiant heat transfer can be increased. For this reason, the heat dissipation to the circumference | surroundings of the heat-transfer support members 32 and 33 and the baseplate part 34 is activated, and the heat cooling of the control circuit board 22 and the power supply circuit board 23 can be performed efficiently. In addition, you may make it make the surface of only the heat-transfer support members 32 and 33 black except for the baseplate part 34. FIG.

The heat transfer support member 32 includes a heat transfer support plate portion 32a on a flat plate, and a heat transfer support side plate portion fixed to the right end side of the heat transfer support plate portion 32a along the long side of the semiconductor power module 11 with a fixing screw 32b. 32c. The heat transfer support side plate portion 32 c is connected to the common bottom plate portion 34.
The control circuit board 22 is fixed to the heat transfer support plate portion 32 a by a fixing screw 36 via a heat transfer member 35. The heat transfer member 35 is an elastic body having elasticity, and has the same outer dimensions as the power circuit board 23. As this heat transfer member 35, a member having improved heat transfer performance while exhibiting insulating performance by interposing a metal filler inside silicon rubber is applied.

The heat transfer support side plate portion 32c is integrally connected to the outer peripheral edge on the long side of the common bottom plate portion 34 disposed in the circumferential groove 3d of the cooling body 3, and extends upward. An upper plate portion 32e extending leftward from the upper end of the connecting plate portion 32d is formed in an inverted L-shaped cross section. The connecting plate portion 32 d extends upward through the right side surface on the long side of the semiconductor power module 11.
The heat transfer support member 33 includes a heat transfer support plate portion 33a on a flat plate, and a heat transfer support side plate portion fixed to the left end side of the heat transfer support plate portion 33a along the long side of the semiconductor power module 11 with a fixing screw 33b. 33c. The heat transfer support side plate portion 33 c is connected to the common bottom plate portion 34.

The power supply circuit board 23 is fixed to the heat transfer support plate portion 33a by a fixing screw 38 via a heat transfer member 37 similar to the heat transfer member 35 described above.
Further, the heat transfer support side plate portion 33c is integrally connected to the outer peripheral edge on the long side of the common bottom plate portion 34 disposed in the circumferential groove 3d of the cooling body 3, and extends upward. An upper plate portion 33e extending leftward from the upper end of the connecting plate portion 33d is formed in an inverted L-shaped cross section. The connecting plate portion 33 d extends upward through the left side surface on the long side of the semiconductor power module 11.

And the connection part with the bottom board part 34 and the upper board part 33e of the connection board part 33d is formed in the curved surfaces 33f and 33g which are a part of cylindrical surface, for example. Thus, by making the connecting portions of the connecting plate portion 33d, the bottom plate portion 34, and the upper plate portion 33e into cylindrical curved surfaces 33f and 33g, it is possible to improve vibration resistance against vertical vibration and roll. . That is, it is possible to alleviate the stress concentration generated in the connecting portion between the connecting plate portion 33d, the bottom plate portion 34, and the upper plate portion 33e when vertical vibration or roll is transmitted to the power conversion device 1.

Further, by connecting the connecting plate portion 33d to the bottom plate portion 34 and the upper plate portion 33e with cylindrical curved surfaces 33f and 33g, the connecting portion between the connecting plate portion 33d and the bottom plate portion 34 and the upper plate portion 33e. The heat conduction path can be shortened as compared with the case of forming a right-angle L-shape. For this reason, the heat conduction path from the heat transfer support plate portion 33a to the cooling body 3 is shortened, and efficient heat cooling becomes possible.

Further, on the control circuit board 22 and the power circuit board 23, a heat generating circuit component 39 is mounted on the upper surface side as shown in FIGS.
Then, the control circuit board 22 and the power supply circuit board 23 are connected to the heat transfer members 35 and 37 and the heat transfer support plate portions 32a and 33a as shown in FIG. The connection between the control circuit board 22 and the power circuit board 23 and the heat transfer support plate portions 32a and 33a is substantially the same except that the left and right are reversed. The plate portion 33a will be described as a representative.

As shown in FIGS. 2 and 3, the connection between the power supply circuit board 23 and the heat transfer support plate 33 a has a heat transfer plate portion management height H lower than the thickness T of the heat transfer member 37. A spacer 40 is used. The spacer 40 is temporarily fixed by bonding or the like to the outer peripheral side of the female screw portion 41 into which the fixing screw 38 formed on the heat transfer support plate portion 33a is screwed. Here, the heat transfer plate portion management height H of the spacer 40 is set so that the compression rate of the heat transfer member 37 is about 5 to 30%. Thus, by compressing the heat transfer member 37 to about 5 to 30%, the thermal resistance is reduced and an efficient heat transfer effect can be exhibited.

On the other hand, the heat transfer member 37 is formed with an insertion hole 37 a through which the joint screw 25 can be inserted and an insertion hole 37 b through which the spacer 40 can be inserted.
The heat transfer member 37 is placed on the heat transfer support plate 33a so that the spacer 40 temporarily fixed to the heat transfer support plate 33a is inserted into the insertion hole 37b. The power supply circuit board 23 is placed thereon so that the heat generating circuit component 39 is in contact with the heat transfer member 37.

In this state, the fixing screw 38 is screwed into the female screw portion 41 of the heat transfer support plate portion 33a through the insertion hole 23b of the power circuit board 23 and the central opening of the spacer 40. Then, the fixing screw 38 is tightened until the upper surface of the heat transfer member 37 substantially coincides with the upper surface of the spacer 40.
For this reason, the heat transfer member 37 is compressed at a compression rate of about 5 to 30%, and the heat resistance is reduced and an efficient heat transfer effect can be exhibited. At this time, since the compression rate of the heat transfer member 37 is managed by the height H of the spacer 40, appropriate tightening is performed without causing insufficient tightening or excessive tightening.

The connection through the heat transfer member 35 between the control circuit board 22 and the heat transfer support plate portion 32a is performed in the same manner as described above.
Note that the distance between the control circuit board 22 and the power supply circuit board 23 is such that the upper end of the circuit component 42 mounted on the control circuit board 22 and serving as a reference is relatively low and the heat transfer support member of the power supply circuit board 23. The distance from the lower surface of the 33 heat transfer support plate portion 33a is set to a necessary insulation distance L1.
For this reason, in the heat generating circuit component 39 having a height higher than the reference circuit component 42, the distance L2 is shorter than the necessary insulation distance L1, and the heat generating circuit component 39 and the heat transfer support plate portion 33a of the power circuit board 23 are connected to each other. The gap is an insufficient insulation distance region.

If this insulation distance shortage region is left as it is, insulation failure will occur, so an insulation securing region is formed in the insulation distance shortage region. As the insulation securing region, in the configuration of FIG. 1, an insulating sheet 43 larger than the planar shape of the heat generating circuit component 39 is attached to the heat transfer support plate 33 a of the power circuit board 23 facing the upper surface of the heat generating circuit component 39. Etc. are arranged. Thus, by disposing the insulating sheet 43 on the heat transfer support plate portion 33a facing the insulation distance shortage region, the shortage of insulation distance can be solved, and the most prominent heating circuit component 39 and the heat transfer facing the heat transfer circuit component 39 can be solved. It is possible to reliably insulate the heat support plate portion 33a.

Further, as shown in FIGS. 2 and 3, the common bottom plate portion 34 of the heat transfer support members 32 and 33 is inserted through the fixing member at a position facing the insertion hole 15 through which the fixing screw 14 of the semiconductor power module 11 is inserted. A hole 34a is formed. Further, a plate-like elastic member 45 is interposed between the upper surface of the bottom plate portion 34 and the lower surface of the heat dissipation member 13 formed in the semiconductor power module 11.
Then, the fixing screw 14 is inserted into the insertion hole 15 of the semiconductor power module 11 and the heat radiating member 13 and the fixing member insertion hole 34 a of the bottom plate portion 34, and the fixing screw 14 is screwed into the female screw portion 3 f formed in the cooling body 3. By doing so, the semiconductor power module 11 and the bottom plate portion 34 are fixed to the cooling body 3.

Next, a method for assembling the power conversion device 1 according to the first embodiment will be described.
First, as described above with reference to FIG. 2, the power supply circuit board 23 is superposed on the heat transfer support plate portion 33a of the heat transfer support member 33 via the heat transfer member 37, and the heat transfer member 37 is placed on the heat transfer member 37 by the fixing screw 38. The power supply circuit board 23, the heat transfer member 37, and the heat transfer support plate 33a are fixed in a state compressed at a compression rate of about%, and the power supply circuit unit U3 is formed as shown in FIG.
Similarly, the control circuit board 22 is superposed on the heat transfer support plate portion 32a of the heat transfer support member 32 via the heat transfer member 35, and the heat transfer member 35 is compressed by a fixing screw 36 at a compression ratio of about 5 to 30%. In this state, the control circuit board 22, the heat transfer member 35, and the heat transfer support plate 32a are fixed to form the control circuit unit U2.

On the other hand, in the circumferential groove 3 d of the cooling body 3, a bottom plate portion 34 common to the heat transfer support members 32 and 33 is provided between the upper surface and the lower surface of the heat radiating member 13 formed in the semiconductor power module 11. In the state where 45 is interposed, it is fixed with the fixing screw 14 together with the semiconductor power module 11. Thus, since the semiconductor power module 11 and the common bottom plate portion 34 of the heat transfer support members 32 and 33 can be fixed to the cooling body 3 at the same time, the number of assembling steps can be reduced.

Further, since the plate-like elastic member 45 is interposed between the bottom plate portion 34 and the heat dissipation member 13 of the semiconductor power module 11 when the bottom plate portion 34 is fixed to the cooling body 3, the plate-like elastic member 45 causes the bottom plate portion 34 to be interposed. Is pressed against the bottom of the circumferential groove 3d of the cooling body 3, and the bottom plate portion 34 is reliably brought into contact with the cooling body 3, thereby ensuring a wide contact area.

In the semiconductor power module 11, the drive circuit board 21 is mounted on the board fixing part 16 formed on the upper surface of the semiconductor power module 11 before or after fixing to the cooling body 3. Then, the drive circuit board 21 is fixed to the board fixing portion 16 by four joint screws 24 from above. And the heat-transfer support plate part 32a is connected with the heat-transfer support side plate part 32c with the fixing screw 32b.
Then, the control circuit board 22 of the control circuit unit U <b> 2 is placed on the upper surface of the joint screw 24 and is fixed by the four joint screws 25. Further, the power supply circuit board 23 of the power supply circuit unit U 3 is placed on the upper surface of the joint screw 25 and fixed by the four fixing screws 26. And the heat-transfer support plate part 33a is connected with the heat-transfer support side plate part 33c by the fixing screw 33b.

Thereafter, although not shown, a DC power source such as an external converter is connected to the positive and negative DC input terminals of the semiconductor power module 11 and the positive and negative terminals of the film capacitor 4 are connected.
Furthermore, a load such as a three-phase electric motor outside the three-phase AC output terminal (not shown) of the semiconductor power module 11 is connected.
Thereafter, the lower housing 2A and the upper housing 2B are fixed to the lower surface and the upper surface of the cooling body 3 via a sealing material, and the assembly of the power conversion device 1 is completed.

In this state, DC power is supplied from an external converter (not shown), and the power supply circuit mounted on the power supply circuit board 23 and the control circuit mounted on the control circuit board 22 are set in an operating state. A gate signal that is a pulse width modulation signal is supplied to the semiconductor power module 11 via a drive circuit mounted on the drive circuit board 21. As a result, the IGBT built in the semiconductor power module 11 is controlled to convert DC power into AC power. The converted AC power drives and controls a load (not shown) such as a three-phase electric motor from a three-phase AC output terminal.

At this time, the IGBT built in the semiconductor power module 11 generates heat. This heat generation is cooled by the cooling water supplied to the cooling body 3 because the heat radiating member 13 formed in the semiconductor power module 11 is in direct contact with the central portion 3 c of the cooling body 3.
On the other hand, the control circuit and the power supply circuit mounted on the control circuit board 22 and the power supply circuit board 23 include a heat generating circuit component 39, and the heat generating circuit component 39 generates heat. At this time, the heat generating circuit component 39 is mounted on the upper surface side of the control circuit board 22 and the power supply circuit board 23.

The heat transfer support plate portions 32a and 33a of the heat transfer support members 32 and 33 are provided on the lower surface sides of the control circuit board 22 and the power supply circuit board 23 through heat transfer members 35 and 37 having high thermal conductivity and elasticity. Is provided.
For this reason, the heat generated by the heat generating circuit component 39 is efficiently transferred to the heat transfer members 35 and 37. Since the heat transfer members 35 and 37 themselves are compressed at a compression rate of about 5 to 30% to increase the thermal conductivity, the heat transferred to the heat transfer members 35 and 37 is efficiently supported by the heat transfer. It is transmitted to the heat transfer support plate portions 32a and 33a of the members 32 and 33.

And since the heat transfer support side plate portions 32c and 33c are connected to the heat transfer support plate portions 32a and 33a, the heat transferred to the heat transfer support plate portions 32a and 33a is transferred to the heat transfer support side plate portions 32c and 33a. It is transmitted to the common bottom plate part 34 through 33c. Since the bottom plate portion 34 is in direct contact with the circumferential groove 3 d of the cooling body 3, the transmitted heat is radiated to the cooling body 3.
Further, the heat transmitted to the bottom plate portion 34 is transmitted from the upper surface side to the heat radiating member 13 of the semiconductor power module 11 via the plate-like elastic member 45, and the central portion 3 c of the cooling body 3 is transmitted via the heat radiating member 13. It is transmitted to and dissipated.

Thus, according to the first embodiment, the heat generation of the heat generating circuit component 39 mounted on the control circuit board 22 and the power circuit board 23 is caused by the heat transfer member 35 and the heat transfer member 35 via the control circuit board 22 and the power circuit board 23. Since heat is transferred to 37, efficient heat dissipation can be performed.
The heat transferred to the heat transfer members 35 and 37 is transferred to the heat transfer support plate portions 32a and 33a, and further transferred to the heat transfer support side plate portions 32c and 33c. At this time, the heat transfer support side plate portions 32 c and 33 c are provided along the long side of the semiconductor power module 11.

For this reason, a wide heat transfer area can be taken, and a wide heat dissipation path can be secured. Moreover, since the bent portions of the heat transfer support side plate portions 32c and 33c are cylindrical curved portions, the heat transfer distance to the cooling body 3 is shortened as compared with the case where the bent portions are L-shaped. Can do. Here, the heat transport amount Q can be expressed by the following equation (1).
Q = λ × (A / L) × T (1)
Where λ is the thermal conductivity [W / m ° C.], T is the temperature difference [° C.] substrate temperature T 1 -cooling body temperature T 2, A is the minimum heat transfer cross section [m ² ], and L is the heat transfer length [m ].

As is clear from the equation (1), when the heat transfer length L is shortened, the heat transport amount Q is increased, and a good cooling effect can be exhibited.
Further, since the heat transfer support side plate portions 32c and 33c of the heat transfer support members 32 and 33 are integrated by the common bottom plate portion 34, the components are arranged between the heat transfer support side plate portions 32c and 33c and the bottom plate portion 34. The heat resistance can be suppressed.

Furthermore, since the housing 2 is not included in the heat dissipation path from the control circuit board 22 and the power circuit board 23 on which the heat generating circuit component 39 is mounted to the cooling body 3, the housing 2 is required to have heat conductivity. Absent. Therefore, it is not necessary to use a metal having a high thermal conductivity such as aluminum as a constituent material of the casing 2, and the casing 2 can be configured with a synthetic resin material, and the weight can be reduced.
Further, since the heat dissipation path can be formed by the power conversion device 1 alone without the heat dissipation path being dependent on the housing 2, the semiconductor power module 11, the drive circuit board 21, the control circuit board 22, and the power supply circuit board 23. Can be applied to the housing 2 and the cooling body 3 in various different forms.

Further, since the metal heat transfer support plate portions 32a and 33a are fixed to the control circuit board 22 and the power circuit board 23, the rigidity of the control circuit board 22 and the power circuit board 23 can be increased. For this reason, the heat transfer support members 32 and 33 can be used even when vertical vibration or roll is applied to the power conversion device 1 as in the case where the power conversion device 1 is applied as a motor drive circuit for driving a vehicle driving motor. Can increase the rigidity. Therefore, it is possible to provide the power conversion device 1 that is less affected by vertical vibrations and rolls.

The heat generated by the heat generating circuit component 39 mounted on the upper surface of the control circuit board 22 is also radiated to the space between the control circuit board 22 and the power supply circuit board 23, and this heat dissipation is transferred to the power supply circuit board 23 facing the heat supply circuit board 23. The heat is absorbed by the support plate portion 33a and radiated to the cooling body 3 through the heat transfer support side plate portion 33c. Therefore, heat generated by the heat generating circuit component 39 is not dissipated between the control circuit board 22 and the power supply circuit board 23 and is radiated to the cooling body 3.

Here, the distance between the control circuit board 22 and the power supply circuit board 23 is set to the necessary insulation distance L1 between the upper surface of the reference circuit component 42 and the heat transfer support plate 33a of the power supply circuit board 23. Yes. Therefore, insulation is ensured between the circuit component 42 and the heat transfer support plate portion 33a of the power supply circuit board 23, but the insulation distance is higher for the circuit component 39 that is higher than the reference circuit component 42. It cannot be secured.

However, in this embodiment, when the insulation distance shortage region occurs, the insulation sheet 43 is disposed on the opposing surface of the heat transfer support plate portion of the power supply circuit board 23 facing the insulation distance shortage region. A necessary heat transfer distance is secured by the sheet 43.
For this reason, the distance between the control circuit board 22 and the power supply circuit board 23 is a distance obtained by adding the necessary insulation distance L1 to the height of the reference circuit part 42, and the heat generating circuit part 39 having the shortest insulation distance. The distance can be sufficiently shorter than the distance obtained by adding the necessary insulation distance L1 to the height.

For this reason, the distance from the semiconductor power module 11 to the uppermost power circuit board 23 can be shortened, and the height of the upper casing 2B surrounding them can also be lowered, so that compactness can be achieved. .
In the first embodiment, the case where there are two types of boards on which the heat generating circuit component 39 is mounted has been described. However, the present invention is not limited to the above-described configuration, and the present invention can be applied even when the substrate on which the heat generating circuit component 39 is mounted is, for example, only one control circuit substrate 22 or three or more substrates. Is something that can be done.

Next, a second embodiment of the present invention will be described with reference to FIG.
In the second embodiment, when the mounted circuit component is high and an insufficient insulation region occurs, an insulating heat transfer member is interposed in the region facing the insufficient insulation region to ensure insulation. It is a thing.
That is, in the second embodiment, as shown in FIG. 4, the insulating sheet 43 in the first embodiment described above is omitted, and instead, the circuit component having the highest height mounted on the control circuit board 22. Insulation having insulation properties similar to those of the heat transfer members 35 and 37 in the first embodiment described above in a region where the insulation distance is insufficient between 39 and the heat transfer support plate portion 33a of the power supply circuit board 23 opposed thereto. An insulation ensuring region is formed by interposing the heat transfer member 51. Since the configuration other than this is the same as that of the first embodiment described above, the same reference numerals are given to the corresponding parts in FIG. 4 with FIG. 1, and the detailed description thereof will be omitted.

Also in the second embodiment, insulation is performed in an insufficient insulation distance region between the circuit component 39 having the highest height between the control circuit board 22 and the power circuit board 23 and the heat transfer support plate portion 33a of the power circuit board 23. Since the heat conductive member 51 is interposed, the insulating heat transfer member 51 can ensure insulation in the region where the insulation distance is insufficient.

In addition, in this case, since the insulating heat transfer member 51 is interposed between the circuit component 39 and the heat transfer support plate portion 33a of the power circuit board 23, the insulation is not only ensured but also the insulating property. When the heat transfer member 51 can be used as a heat dissipation path and the circuit component 39 having the highest height is a heat generating circuit component, the heat generation is directly transmitted through the insulating heat transfer member 51. Heat can be transferred to 33a, and heat dissipation of the heat generating circuit components can be performed more effectively.
In the second embodiment, the case where the insulating heat transfer member 51 is applied as the insulation securing region has been described. However, the present invention is not limited to this, and an insulating member having a low thermal conductivity is used. You may do it.

Next, a third embodiment of the present invention will be described with reference to FIGS.
In the third embodiment, the heat transfer support plate portion 33a of the power supply circuit board 23 facing the insulation distance shortage region is removed as the insulation ensuring region.
That is, in the third embodiment, as shown in FIG. 5, the upper end of the highest circuit component 39 mounted on the control circuit board 22 and the heat transfer support plate portion 33a of the power circuit board 23 are arranged. As shown in FIG. 6 (a) or (b), the heat transfer support plate portion 33a at the position facing the circuit component 39 in the region where the insulation distance is short between is a rectangular cut portion larger than the planar shape of the circuit component 39. The insulating distance is ensured by forming 61a or forming a circular cut portion 61b larger than the planar shape of the circuit component 39 to expose the heat transfer member 37.

Since other configurations have the same configurations as those of the first embodiment and the second embodiment described above, the same reference numerals are given to corresponding portions to those in FIGS. 1 and 4 and detailed description thereof is omitted. To do.
According to the third embodiment, in the region where the insulation distance is insufficient between the upper surface of the circuit component 39 mounted on the control circuit board 22 and the heat transfer support plate portion 33a of the power circuit board 23, Since the heat transfer plate 37 is cut out to expose the heat transfer member 37, the insulation distance of the heat transfer member 37 can be secured. For this reason, the same effect as the 1st and 2nd embodiment mentioned above can be acquired. In addition to this, the insulating sheet 43 and the insulating heat transfer member 51 are not required, and the heat transfer support plate portion 33a may be simply cut away, so that no part cost is required and the cost can be reduced. .

In the third embodiment, the case where the shape of the heat transfer support plate 33a to be cut out is a rectangle or a circle. However, the shape is not limited to this, and a predetermined insulation distance can be secured. It can be of any shape.
In the first to third embodiments, the case where there are two types of substrates on which the heat generating circuit component 39 is mounted has been described. However, the present invention is not limited to the above-described configuration, and the present invention can be applied even when the substrate on which the heat generating circuit component 39 is mounted is, for example, only one control circuit substrate 22 or three or more substrates. Is something that can be done.

In the first to third embodiments, the heat transfer support members 32 and 33 are composed of separate heat transfer support plate portions 32a and 33a and heat transfer support side plate portions 32c and 33c. Although it demonstrated, it is not limited to this, You may make it form the heat-transfer support plate part 32a, 33a and the heat-transfer support side plate part 32c, 33c integrally. In this case, since there is no seam between the heat transfer support plate portions 32a and 33a and the heat transfer support side plate portions 32c and 33c, the thermal resistance can be reduced and the heat dissipation effect can be further improved. .

In the first to third embodiments, the case where the power conversion device according to the present invention is applied to an electric vehicle has been described. However, the present invention is not limited to this, and the present invention is also applied to a rail vehicle traveling on a rail. The invention can be applied and can be applied to any electric drive vehicle. Furthermore, the power conversion device is not limited to an electrically driven vehicle, and the power conversion device of the present invention can be applied when driving an actuator such as an electric motor in other industrial equipment.

According to the present invention, even when an insulation distance shortage region where the insulation distance is partially insufficient between the mounting boards is formed, insulation is ensured in the insulation ensuring region, so that heat transfer is performed at a position facing the heating circuit component. It is possible to dissipate heat to the cooling body without exposing the heat generation of the heat generating circuit components on the opposite surface by exposing the support member, improving the heat dissipation effect and the insulation distance that requires the distance between the mounting boards It is possible to provide a power conversion device that can be shortened and can be made compact.

DESCRIPTION OF SYMBOLS 1 ... Power converter device, 2 ... Housing, 3 ... Cooling body, 4 ... Film capacitor, 11 ... Semiconductor power module, 12 ... Case body, 13 ... Heat dissipation member, 21 ... Drive circuit board, 22 ... Control circuit board, 23 ... Power circuit board, 24, 25 ... Joint screw, 32 ... Heat transfer support member, 32a ... Heat transfer support plate portion, 32b ... Fixing screw, 32c ... Heat transfer support side plate portion, 33 ... Heat transfer support member, 33a ... Transfer Heat support plate, 33b ... Fixing screw, 33c ... Heat transfer support side plate, 34 ... Bottom plate, 35, 37 ... Heat transfer member, 39 ... Heating circuit component, 40 ... Spacer (spacing adjustment member), 42 ... Reference Circuit parts that become 43 ... Insulating sheet, 45 ... Plate-like elastic member, 51 ... Insulating heat transfer member, 61a, 61b ... Cut part

Claims (9)

1. A semiconductor power module that joins one surface to a cooling body;
   A plurality of mounting boards on which circuit components including heat generating circuit components for driving the semiconductor power module are mounted;
   Heat transferred to a plurality of mounting substrates to the cooling body, and a heat transfer support member;
   Between the plurality of mounting boards, an insulation securing region formed in an insulation distance shortage region where the insulation distance is short, and
   A power conversion device comprising:
2. The power conversion device according to claim 1, wherein the insulation securing region is a region that secures insulation by interposing an insulating heat transfer member at a position facing the insulation distance shortage region.
3. The power conversion device according to claim 1, wherein the insulation securing region is a region that secures insulation by disposing an insulating sheet at a position facing the insulation distance shortage region.
4. The power conversion device according to claim 1, wherein the insulation ensuring region is a region that secures insulation by removing the heat transfer support member at a position facing the insulation distance shortage region.
5. The heat transfer support member includes a heat transfer support plate portion that supports the mounting substrate via the heat transfer member, and a heat transfer support side plate portion that is connected to the cooling body by connecting side surfaces of the heat transfer support plate portion. The power conversion device according to any one of claims 1 to 4, wherein the power conversion device is configured.
6. The power conversion device according to claim 5, wherein the heat transfer support plate portion and the heat transfer support side plate portion are integrally formed.
7. The power conversion device according to claim 5, wherein the heat transfer member is made of an insulating material.
8. The power conversion device according to claim 5, wherein the mounting substrate and a heat transfer support plate portion of the heat transfer support member are fixed by a tightening fixing member via the heat transfer member.
9. 9. An interval adjusting member for maintaining an interval between the mounting substrate and the heat transfer support plate portion of the heat transfer support member at a predetermined value is interposed around the tightening fixing member. The power converter described.

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