JP6904082B2 - Power converter - Google Patents

Description

The present invention relates to a power conversion device, and more particularly to a power conversion device including a semiconductor element.

In the power distribution system, as a power conversion device, a static power compensator (Static Var Compensator, hereinafter referred to as “SVC”) having a function of suppressing voltage fluctuations by high-speed static power output control is used. By connecting such an SVC to a distribution system, it is expected to suppress abrupt voltage fluctuations (see Patent Document 1).

As the SVC, a structure including a semiconductor element that performs power conversion and a housing that forms a closed space around the semiconductor element is known. Since the semiconductor element generates heat during power conversion and becomes hot, it is attached to a cooling body such as a heat sink to be cooled.

The cooling body is provided with a plurality of heat radiation fins on one surface of the base plate, and the other surface of the base plate is formed as a mounting surface on which the semiconductor element is mounted. The cooling body is assembled with the housing so that the semiconductor elements mounted on the mounting surface are housed in the housing while the heat radiation fins are exposed outside the housing. As a result, the heat of the semiconductor element is transmitted from the base plate to the outside of the housing through the heat radiation fins, and the deterioration of the performance and durability of the semiconductor element is suppressed.

Japanese Unexamined Patent Publication No. 2014-33492

In the SVC having the above-mentioned structure, the mounting surface of the cooling body, which is a heat source, becomes close to the electronic circuit or the like in the housing due to the heat generated from the semiconductor element, and the electronic circuit or the like in the housing tends to become hot. There is a problem. In addition, if the electronic circuit in the housing and the semiconductor element are physically isolated, the semiconductor element cannot be accessed and work such as removing the cooling body is required. Therefore, maintenance after installation of the device is required. It will be difficult.

The present invention has been made in view of such a problem, and provides a power conversion device capable of ensuring maintainability while suppressing the thermal influence from the mounting surface of the cooling body to which the semiconductor element is mounted. One of the purposes is to provide.

The power conversion device of one aspect of the present invention includes a semiconductor element, a mounting surface on which the semiconductor element is mounted, a cooling body that releases heat of the semiconductor element, and the mounting surface so as to surround the semiconductor element. It is characterized by having a spacer and a heat insulating member that fills a space in which the semiconductor element is not mounted among the mounting surfaces surrounded by the spacer.

Further, the power conversion device of another aspect of the present invention includes a semiconductor element, a mounting surface on which the semiconductor element is mounted, a cooling body that releases heat from the semiconductor element, and the semiconductor element so as to surround the semiconductor element. It is characterized by having a spacer provided on the mounting surface and a heat-insulated partition wall attached to the cooling body via the spacer.

According to these configurations, since the spacer is provided on the mounting surface of the cooling body, the mounting surface as a heat source and various circuits and parts located on the mounting surface side should be separated by the width and thickness of the spacer. Can be done. As a result, even if the mounting surface becomes hot due to heat generated from the semiconductor element, the amount of heat transferred to various circuits on the mounting surface side can be reduced, and the high temperature can be avoided and the thermal influence can be suppressed. .. Moreover, it is possible to prevent the heat generated from the mounting surface from flowing in by the heat insulating member or the heat insulating partition wall, and this also suppresses the thermal influence on various circuits and the like from the mounting surface side.

Further, the power conversion device of another aspect of the present invention includes a semiconductor element, a mounting surface on which the semiconductor element is mounted, a cooling body that releases heat from the semiconductor element, and a mounting surface side of the cooling body. It has a housing located in the above, and a heat-insulated partition wall provided between the cooling body and the housing and physically connecting the cooling body and the housing while electrically insulating them. The cooling body and the housing are electrically insulated by the heat-insulating partition wall. According to this configuration, it is possible to prevent the heat generated from the mounting surface by the heat insulating partition wall from flowing into the housing, and it is possible to suppress the thermal influence from the mounting surface side on various circuits in the housing. ..

According to the power conversion device of the present invention, since the spacer and the heat insulating partition wall are provided on the mounting surface of the cooling body to which the semiconductor element is mounted, the thermal influence from the mounting surface of the cooling body can be suppressed. Further, by making the configuration easy to access the semiconductor element after mounting the device, maintainability can be ensured even after the device is installed.

It is a top view of the power conversion apparatus which concerns on 1st Embodiment. FIG. 1 is a cross-sectional view taken along the line AA of FIG. FIG. 2 is a cross-sectional view taken along the line BB of FIG. FIG. 5 is a cross-sectional view taken along the line CC of FIG. It is a top view of the power conversion apparatus which concerns on 2nd Embodiment. FIG. 5 is a cross-sectional view taken along the line DD of FIG. 5 in which the housing is omitted. FIG. 6 is a cross-sectional view taken along the line EE of FIG. It is the same cross-sectional view as FIG. 2 which shows the spacer which concerns on 1st modification. It is the same cross-sectional view as FIG. 2 which shows the spacer which concerns on 2nd modification. It is a top sectional view of the power conversion apparatus which concerns on 3rd modification. It is sectional drawing for explanation for explanation of the frame member which concerns on 4th modification. It is sectional drawing for explanation for explanation of the frame member which concerns on 5th modification.

Hereinafter, the power conversion device according to the embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following, a case where the power conversion device according to the present invention is applied to an SVC (Static Variety Compensator) will be described. However, the application target of the power conversion device according to the present invention is not limited to SVC, and can be changed as appropriate. For example, it can be applied to all power conversion devices using semiconductors such as power conversion devices other than SVC, voltage regulators, inverter devices, and converter devices.

[First Embodiment]
FIG. 1 is a plan view of the power conversion device according to the first embodiment. As shown in FIG. 1, the power conversion device 10 includes a rectangular parallelepiped housing 11 and a cooling body 12 attached to the upper side of the housing 11 in FIG. A plate-shaped heat insulating partition wall 13 is interposed between the housing 11 and the cooling body 12. The heat insulating partition wall 13 is made of a material having a low thermal conductivity, and specific examples thereof include FRP using a polyester-based or epoxy-based resin material as a base material, and a resin material such as acrylic or polycarbonate. Further, the heat insulating partition wall 13 is preferably made of a material capable of exhibiting electrical insulation performance.

A mounting reinforcing member 15 is provided on the outer peripheral side of the cooling body 12. The mounting reinforcing member 15 is formed of an angle member (see FIG. 3), is fixed to the heat insulating partition wall 13 by screwing or the like, and is arranged along the outer edge of the cooling body 12. The mounting reinforcing member 15 may be partially or completely omitted as long as the cooling body 12 is mounted on the heat insulating partition wall 13 by the spacer 18 (see FIG. 3) described later.

FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line BB of FIG. In FIG. 2, the mounting reinforcing member 15 is not shown. As shown in FIGS. 2 and 3, the cooling body 12 includes a base plate 12a having a square plate shape. A plurality of heat radiation fins 12b (not shown in FIG. 2) are formed on one surface of the base plate 12a (upper surface in FIG. 3) so as to extend in the direction orthogonal to the paper surface of FIG. The cooling body 12 is formed of a material having high thermal conductivity, and specifically, a metal such as aluminum can be exemplified.

The other surface (lower surface in FIG. 3) of the base plate 12a is a mounting surface 12c, and four semiconductor elements 17, two spacers 18, and six heat insulating members 19 are attached to the mounting surface 12c. There is.

The semiconductor element 17 is an element used in SVC to perform electric power conversion, and is formed in a state of being packaged with a resin material. In the semiconductor element 17, the surface facing the mounting surface 12c is formed of metal or the like as a heat radiating surface, and the heat generated during power conversion is mainly released from the heat radiating surface. Then, the heat radiating surface of the semiconductor element 17 is mounted in a state of surface contact with the mounting surface 12c, the heat of the semiconductor element 17 is transferred from the mounting surface 12c to the base plate 12a and the heat radiating fins 12b, and the heat radiating fins 12b are exposed to the outside air and released. Will be done.

As shown in FIG. 2, four semiconductor elements 17 are mounted side by side on the mounting surface 12c. Further, the spacer 18 is provided on the mounting surface 12c so as to surround the semiconductor element 17. Specifically, when the four semiconductor elements 17 are divided into groups, the two semiconductor elements 17 arranged vertically on the left side and the two semiconductor elements 17 arranged vertically on the right side are divided into groups. The spacer 18 is formed so as to surround the four sides of each group. Therefore, two spacers 18 are provided in the shape of a vertically long frame in FIG. 2, and two semiconductor elements 17 are arranged inside each spacer 18. The left-right width of the opening 18a surrounded by the spacer 18 is formed to be substantially the same as or slightly larger than the left-right width of the semiconductor element 17. On the other hand, the terminal positions of the semiconductor element 17 are on both the upper and lower sides, and the vertical width of the opening 18a is formed so as to be separated from the semiconductor element 17 in order to secure the insulation distance between the terminal and the spacer 18. In addition, depending on the restriction of insulation between the spacer 18 and the semiconductor element 17, the shape of the opening 18a may be widened or narrowed in the vertical and horizontal directions between them.

The heat insulating member 19 is attached so as to fill the space in which the semiconductor element 17 is not attached in the attachment surface 12c surrounded by the spacer 18. Specifically, it is provided on both the upper and lower sides of the semiconductor element 17 inside the opening 18a of the spacer 18, and is provided so that the mounting surface 12c is not exposed inside the opening 18a in FIG. Examples of the heat insulating member 19 include cotton-like materials such as glass wool and materials having extremely low thermal conductivity such as foams containing a large number of bubbles.

As shown in FIG. 3, the spacer 18 is formed by a frame member 21 having a channel shape (U shape) having a mainly constant cross section and extending in the longitudinal direction. Specifically, the frame member 21 includes a pair of parallel portions 21a and 21b arranged at predetermined intervals, and a connecting portion 21c that connects one ends of the parallel portions 21a and 21b. The frame member 21 forms an opening 18a of the spacer 18 on the connecting portion 21c side, and is formed so that the side opposite to the connecting portion 21c is open. For example, the frame member 21 is made of a molded body made of a resin material, a steel material, or a sheet metal processing material.

The parallel portion 21a of the frame member 21 on the cooling body 12 side (upper side in FIG. 3) is fixed by a mounting member (not shown) such as a screw in a state of being in contact with the mounting surface 12c of the cooling body 12. The parallel portion 21b of the frame member 21 on the heat insulating partition wall 13 side (lower side in FIG. 3) is fixed by a mounting member (not shown) such as a screw in a state of being in contact with the upper surface of the heat insulating partition wall 13 in FIG. .. By fixing in this way, the cooling body 12 and the heat insulating partition wall 13 are connected with the frame member 21 sandwiched between them. In other words, the cooling body 12 is attached to the heat insulating partition wall 13 via the spacer 18 formed by the frame member 21, and the heat insulating partition wall 13 is attached to the cooling body 12 via the spacer 18.

A closed loop-shaped packing 23 is provided between the parallel portion 21a and the mounting surface 12c of the cooling body 12 at a position surrounding the outside of the opening 18a of the spacer 18. Further, a packing 24 having a closed loop shape is also provided between the parallel portion 21b and the heat insulating partition wall 13 at a position surrounding the outside of the opening 18a of the spacer 18. By providing these packings 23 and 24, airtightness and liquidtightness are maintained between the spacer 18 and the cooling body 12 and the heat insulating partition wall 13, and rainwater and dust can enter the inside of the opening 18a. Avoided. As long as the airtightness and the liquidtightness are maintained in the same manner, other members such as a sealing material may be provided instead of the packings 23 and 24.

With the cooling body 12 attached to the heat insulating partition wall 13 via the spacer 18 as shown in FIG. 3, a space 26 surrounded by the spacer 18, the mounting surface 12c of the cooling body 12, and the heat insulating partition wall 13 is formed. Will be done. In FIG. 3, the spaces indicated by reference numerals 26a to 26c extend in the direction orthogonal to the paper surface in the figure, that is, in the vertical direction. The spaces 26a to 26c are open on both sides in the vertical direction, and are configured as a flow path through which the outside air outside the housing 11 can flow. In the cross-sectional view of FIG. 3, the spaces 26b and 26c appear to be shielded from the side outside air by the mounting reinforcing member 15, but the mounting reinforcing member 15 and the cooling body 12 and the heat insulating partition wall 13 are airtight. Gender is not guaranteed. Therefore, in the spaces 26b and 26c, the outside air may also flow from the side, and the mounting reinforcing member 15 may be provided with a hole so that the outside air can actively flow. Further, if the mounting reinforcing members 15 on both sides in the direction orthogonal to the paper surface (vertical direction) in FIG. 3 are omitted, the outside air will flow better from the vertical direction with respect to the spaces 26a to 26c. Further, also in the frame members 21 located on both the upper and lower sides of the spacer 18 in FIG. 2, a space surrounded by the mounting surface 12c of the cooling body 12 and the heat insulating partition wall 13 (not shown in FIG. 2) is formed. The outside air outside the housing 11 flows into the space.

As shown in FIG. 3, the housing 11 has an opening 11b formed in the peripheral wall 11a on the cooling body 12 side, and a heat insulating partition wall 13 is provided so as to close the opening 11b. When the heat insulating partition wall 13 closes the opening 11b in this way, the cooling body 12 attached to the heat insulating partition wall 13 is located outside the housing 11. The heat-insulated partition wall 13 is provided in surface contact with the outer surface of the peripheral wall 11a, and is not shown in order to maintain airtightness and liquidtightness between them and prevent rainwater and dust from entering the housing 11. Sealing process etc. is done. Although not shown, a substrate, various circuits, and parts for forming an SVC are housed inside the housing 11.

Here, the entire semiconductor element 17 is arranged outward (upper in FIG. 3) from the opening 11b of the housing 11. In other words, the thickness of the spacer 18 and the heat insulating partition wall 13 is set so that the lower middle region of FIG. 3 of the semiconductor element 17 attached to the cooling body 12 does not reach the opening 11b.

FIG. 4 is a cross-sectional view taken along the line CC of FIG. As shown in FIG. 4, the heat insulating partition wall 13 is formed in a shape having four openings 13a. Each opening 13a is formed in a region corresponding to four semiconductor elements 17, and when viewed from a direction orthogonal to the mounting surface 12c, that is, a direction orthogonal to the paper surface of FIG. 4, the entire semiconductor element 17 can be seen at each opening 13a. It is formed in position, size, and shape. At this time, the heat insulating member 19 is hidden by the heat insulating partition wall 13 and is invisible or almost invisible, and is sandwiched between the heat insulating partition wall 13 and the mounting surface 12c of the cooling body 12. The shape of the opening 13a may be formed so that the heat insulating member 19 can be seen in the state of FIG. 4, and is changed to a shape formed by enlarging the openings 13a arranged vertically in FIG. 4 for example. May be good. In short, in the heat insulating partition wall 13, it is sufficient that the opening 13a is formed at least in the region corresponding to the semiconductor element 17.

Here, the spacer 18 is preferably formed of a material having a lower thermal conductivity than the constituent members of the cooling body 12. As an example, when the cooling body 12 is made of aluminum, the spacer 18 is made of a resin material having a lower thermal conductivity than aluminum, iron, or stainless steel. With such a relationship of thermal conductivity, it is possible to reduce the amount of heat that propagates from the cooling body 12 that becomes hot due to the heat generated by the semiconductor element 17 to the housing 11 side through the spacer 18.

In the above configuration, when power conversion is performed by each semiconductor element 17 and the semiconductor element 17 itself generates heat, the heat is transmitted from the base plate 12a of the cooling body 12 to the heat radiating fins 12b, and the heat between the heat radiating fins 12b and the outside air is transmitted. By replacement, heat is released to the outside of the housing 11. At this time, since the base plate 12a becomes hot due to the heat propagation to the base plate 12a, the temperature inside the housing 11 rises due to the heat radiation from the base plate 12a, and the parts and the like inside the housing 11 are also exposed to the high temperature. There is a risk of being radiated.

Regarding this point, in the present embodiment, the spacer 18 and the heat insulating partition wall 13 are interposed between the mounting surface 12c of the cooling body 12 and the housing 11. As a result, the mounting surface 12c of the cooling body 12 is arranged above the internal space of the housing 11 by the thickness of the spacer 18 and the heat insulating partition wall 13 in FIG. 3, and the mounting surface 12c and the components inside the housing 11 are arranged. Can be kept away. As a result, heat dissipation from the base plate 12a can alleviate the thermal influence of the parts inside the housing 11, and it is possible to avoid deterioration of the performance and durability of the parts.

Further, as described above, the heat insulating member 19 and the heat insulating partition wall 13 are provided between the mounting surface 12c of the cooling body 12 and the opening 11b of the housing 11, and the heat insulating action in the thickness direction of these members also causes the heat insulating member 19 and the heat insulating partition wall 13. The heat radiated from the base plate 12a into the housing 11 can be blocked. Further, the space 26 between the mounting surface 12c and the heat insulating partition wall 13 exhibits a heat insulating effect as an air layer, which also suppresses heat dissipation from the base plate 12a into the housing 11.

Further, since the space 26 is formed as a flow path through which the outside air can flow, heat exchange is performed between the spacer 18 and the outside air, and the space leading to the inside of the housing 11 is cooled inside the opening 18a of the spacer 18. be able to. In particular, in the passage extending in the vertical direction, as shown by the dotted arrow in FIG. 2, the flow of outside air is promoted from the lower side to the upper side by the temperature rise, and the cooling action can be obtained better. Moreover, since the spacer 18 surrounds the semiconductor element 17, the region where the semiconductor element 17 and the spacer 18 are adjacent to each other can be widened, and the cooling action can be obtained at a position close to the semiconductor element 17 which is a heat source.

Further, since the frame member 21 of the spacer 18 has a channel-like cross section, the inner space and the outer space 26 of the opening 18a are partitioned by the connecting portion 21c, and the thickness of the partitioned portion can be reduced. it can. As a result, the amount of heat conducted from the mounting surface 12c to the frame member 21 can be suppressed, and heat exchange between the spacer 18 and the outside air can be performed more efficiently.

Further, in FIG. 3, since the spacer 18 is mounted inside the outer edge of the mounting surface 12c, the mounting surface 12c is exposed to the outside air in the region between the outer edge and the spacer 18. In other words, the mounting surface 12c can directly exchange heat with the outside air outside the housing 11, and the cooling effect of the mounting surface 12c can be enhanced.

Further, since the power conversion device 10 as an SVC is provided on a utility pole, maintenance is not easy due to the installation position and the like, and it is not desirable to use a fan having a short product life for heat dissipation. Moreover, since the power conversion device 10 is arranged outdoors and a sealed structure of the housing 11 is required, it is a particularly remarkable problem to reduce the thermal influence, dissipate heat, and perform the cooling action as described above. It can be said that it can be solved.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the following description, the same reference numerals may be used for the same or equivalent components as those in the first embodiment, and the description may be omitted or simplified.

FIG. 5 is a plan view of the power conversion device according to the second embodiment. In the power conversion device 10 according to the second embodiment, the mounting reinforcing member 15, the spacer 18, and the heat insulating member 19 (see FIG. 3) in the power conversion device 10 according to the first embodiment are eliminated. As shown in FIG. 5, in the second embodiment, the heat insulating partition wall 13 is provided in contact with the mounting surface 12c of the cooling body 12. Therefore, in the second embodiment, the heat insulating partition wall 13 is mounted on the mounting surface 12c side of the cooling body 12 with the heat insulating partition wall 13 interposed between the cooling body 12 and the housing 11. Further, the heat insulating partition wall 13 is attached to the opening 11b (see FIG. 7) side of the housing 11.

As described above, the heat-insulated partition wall 13 is made of a material having a low thermal conductivity and capable of exhibiting electrical insulation performance. Therefore, the housing 11 and the cooling body 12 are thermally and electrically insulated by the heat insulating partition wall 13 sandwiched between them.

FIG. 6 is a cross-sectional view taken along the line DD of FIG. 5 in which the housing is omitted. FIG. 7 is a cross-sectional view taken along the line EE of FIG. As shown in FIGS. 6 and 7, in the heat insulating partition wall 13 of the second embodiment, the opening 13a is formed in the region corresponding to the four semiconductor elements 17 as in the first embodiment. ing. Further, a closed loop packing 24 (not shown in FIG. 6) is provided between the mounting surface 12c and the heat insulating partition wall 13 at a position surrounding the outside of the opening 13a, and the cooling body 12 and the heat insulating partition wall 13 are provided. Airtightness and liquidtightness are maintained between them. As long as the airtightness and the liquidtightness are similarly maintained, another member such as a sealing material may be provided around the contact portion between the cooling body 12 and the heat insulating partition wall 13 instead of the packing 24. The shape and size of the opening 13a are within an allowable range in terms of processing accuracy, assembly accuracy, etc., and the gap between the opening 13a and the outer edge of the semiconductor element 17 is small from the viewpoint of suppressing heat dissipation into the housing 11. It is preferable to set so as to be.

A heat insulating cover 40 is provided on a surface (lower surface in FIG. 7) of the heat insulating partition wall 13 located on the opposite side of the cooling body 12. The heat insulating cover 40 is made of a material having a low thermal conductivity similar to that of the heat insulating partition wall 13 and the heat insulating member 19 described above, and can be formed in a plate shape, a sheet shape, or a lid shape. In the present embodiment, the heat insulating cover 40 is provided as a single piece in a size and shape that covers all four openings 13a. In the state shown in FIG. 7, the thickness of the semiconductor element 17 is set to be within the thickness of the heat-insulated partition wall 13, but the thickness may be larger than the thickness of the heat-insulated partition wall 13. In this case, heat insulation is performed. The cover 40 may be formed so as to bulge downward in FIG. 7 at a portion including the semiconductor element 17. Further, although not shown, the heat insulating cover 40 is formed with a hole or the like through which wiring connected to the semiconductor element 17 is passed.

The heat insulating cover 40 is attached to the heat insulating partition wall 13 by a screw member (detachable member) 40a made of bolts or the like. The screw member 40a penetrates the heat insulating cover 40 and is screwed into the heat insulating partition wall 13, and is detachable from the heat insulating partition wall 13 by a rotational operation around the axis. Therefore, the heat insulating cover 40 is detachably provided on the heat insulating partition wall 13 via the screw member 40a.

The cooling body 12 and the heat insulating partition wall 13 are screwed and fixed by the first screw member (first fixing member) 41, and the heat insulating partition wall 13 and the housing 11 are screwed by the second screw member (second fixing member) 42. It is stopped and fixed. Bolts and various types of screws can be used for the screw members 41 and 42. The first screw member 41 penetrates the heat insulating partition wall 13 from the lower part in FIG. 7 and is screwed into the mounting surface 12c side of the cooling body 12. The second screw member 42 penetrates the peripheral wall 11a around the opening 11b of the heat insulating partition wall 13 and the housing 11 from above in FIG. 7 of the heat insulating partition wall 13, and enters the nut (female screw member) 43 on the inner surface side of the peripheral wall 11a. It is screwed. As a result, the peripheral wall 11a and the heat insulating partition wall 13 are fastened by the second screw member 42 and the nut 43, and the heat insulating partition wall 13 is fixed to the housing 11. In each of the screw members 41 and 42, the members screwed in by rotating around the axis can be detached from each other, and the cooling body 12, the heat insulating partition wall 13, the heat insulating partition wall 13 and the housing 11 can be detached from each other by this attachment / detachment. It is said that it is attached to.

The first screw member 41 is provided at a position along the outer circumference of the heat insulating partition wall 13, and the second screw member 42 is provided at a position along the outer circumference of the mounting surface 12c of the cooling body 12 at a predetermined pitch. The first screw member 41 and the second screw member 42 are arranged at different positions in a plane direction orthogonal to the thickness direction of the heat insulating partition wall 13, that is, in a direction parallel to the paper surface of FIG. In other words, one screw member 41, 42 does not connect both the housing 11 and the cooling body 12.

In the above configuration, the region on the mounting surface 12c of the cooling body 12 to which the semiconductor element 17 is not mounted is covered with the heat insulating partition wall 13. As a result, even if the semiconductor element 17 becomes hot and the base plate 12a of the cooling body 12 generates heat, heat dissipation from the base plate 12a into the housing 11 is blocked by the heat insulating action of the heat insulating partition wall 13, and the housing 11 It is possible to suppress the influence of heat on the internal parts.

Moreover, since the heat-insulated partition wall 13 has electrical insulation performance, a potential difference can be generated between the cooling body 12 and the housing 11, and the cooling body 12 can have the potential of the circuit in the semiconductor element 17. it can. Moreover, since the first screw member 41 and the second screw member 42 are provided at different positions as described above, it is possible to avoid providing a screw member or the like so as to bridge and connect the cooling body 12 and the housing 11. it can. Therefore, due to the member that attaches the cooling body 12 and the heat insulating partition wall 13 to the housing 11, the cooling body 12 and the housing 11 are not energized, and the cooling body 12 and the housing 11 are combined with the insulation performance of the heat insulating partition wall 13. It is possible to guarantee the insulation state with.

Here, in the semiconductor element 17 used in the power conversion device 10, while a high voltage is applied, a potential difference is generated so as to be established as a circuit. Therefore, it is necessary to secure insulation on either the inside or the outside of the semiconductor element 17. is there. Such insulation becomes an extremely high voltage as in the power conversion device 10, and when the semiconductor element 17 becomes thin, the burden on design and manufacturing becomes large in order to secure the insulation in a narrow region in the semiconductor element 17. .. Therefore, if the semiconductor element 17 can be insulated from the outside, the burden on the design and manufacturing can be reduced while the semiconductor element 17 is formed as a circuit.

Regarding this point, in the present embodiment, the insulation between the cooling body 12 outside the semiconductor element 17 and the housing 11 is ensured as described above, so that the insulation inside the semiconductor element 17 is unnecessary. can do. Therefore, it is possible to reduce the burden on the design and manufacture of the semiconductor element 17 while establishing the semiconductor element 17 as a circuit.

Further, since the heat insulating cover 40 is provided, heat dissipation from the mounting surface 12c in the gap between the opening 13a of the heat insulating partition wall 13 and the semiconductor element 17 into the housing 11 can be suppressed. Further, since the heat insulating cover 40 is detachably provided on the heat insulating partition 13, the semiconductor element 17 does not need to remove the heat insulating partition 13 from the housing 11 or the cooling body 12 from the heat insulating partition 13. You will be able to access and perform maintenance. Therefore, the semiconductor element 17 is provided with a member for ensuring liquidtightness and airtightness, such as a packing 24 and a sealing material, between the housing 11 and the heat insulating partition wall 13 and between the heat insulating partition wall 13 and the cooling body 12. It will be accessible. As a result, it is possible to omit the work of replacing the packing 24 and reforming the sealing material each time the semiconductor element 17 is accessed.

The present invention is not limited to the above embodiment, and can be modified in various ways. In the above embodiment, the size, shape, direction, etc. shown in the accompanying drawings are not limited to this, and can be appropriately changed within the range in which the effects of the present invention are exhibited. In addition, it can be appropriately modified and implemented as long as it does not deviate from the scope of the object of the present invention.

Moreover, although each embodiment of the present invention has been described, as another embodiment of the present invention, each of the above embodiments may be combined in whole or in part.

The shape of the spacer 18 in the first embodiment can be changed in various ways. For example, with respect to four semiconductor elements 17, two semiconductor elements 17 arranged side by side on the upper side in FIG. 2 and two semiconductor elements 17 below. When the two semiconductor elements 17 arranged side by side on the left and right sides are divided into groups, the spacers 18 may be formed so as to surround the four sides of each group. Further, the shape of the spacer 18 can be changed to the shape shown in FIGS. 8 and 9. FIG. 8 is a cross-sectional view similar to FIG. 2 showing the spacer according to the first modification, and FIG. 9 is a cross-sectional view similar to FIG. 2 showing the spacer according to the second modification. In the first modification of FIG. 8, all four semiconductor elements 17 are housed and enclosed in the opening 18 of one spacer 18. A heat insulating member 19 is also provided in the space between the semiconductor elements 17 adjacent to the left and right so that the mounting surface 12c is not exposed in the opening 18a. In this configuration, the number of spacers 18 installed and the number of frame members 21 can be reduced, so that the configuration can be simplified and the manufacturing burden can be reduced.

In the second modification of FIG. 9, four spacers 18 are provided so as to surround the four semiconductor elements 17 respectively. In this modification, spacers 18 are arranged adjacent to the four sides of the rectangular semiconductor element 17, and the heat insulating member is omitted. In this configuration, heat exchange through the spacer 18 in the semiconductor element 17 can improve the efficiency of heat exchange by the spacer 18.

Further, the cooling body 12 is not limited to the above-described configuration, and may be changed as long as the heat of the semiconductor element 17 mounted on the mounting surface 12c is released. As an example, the cooling body 12 is changed as shown in FIG. can do. FIG. 10 is a plan sectional view of the power conversion device according to the third modification. In the third modification of FIG. 10, the cooling body 12 is divided into a plurality of bodies (two bodies on the left and right in this modification). Each of the divided cooling bodies 12 is attached to one heat insulating partition wall 13 via the spacer 18, and is in an integrated state. Further, the divided cooling bodies 12 may be in a state of being connected via a connecting plate 30 straddling them. In the third modification, the spacer 18 may be omitted and the cooling bodies 12 and the heat insulating partition walls 13 may be attached to each other.

Further, the cross-sectional shape of the frame member 21 in the spacer 18 can be changed in various ways, for example, the shape shown in FIGS. 11 and 12. FIG. 11 is an explanatory cross-sectional view of the frame member according to the fourth modification, and FIG. 12 is an explanatory sectional view of the frame member according to the fifth modification. In the fourth modification of FIG. 11, the frame member 32 is formed in a tubular shape having a square cross section, and while increasing the strength of the frame member 32 itself, it is provided with a space 32a inside to form a flow path through which outside air flows. doing. In the fifth modification of FIG. 12, the frame member 33 is formed in a solid square columnar shape.

Further, in the power conversion device 10 of the first embodiment, the heat insulating partition wall 13 may be omitted, and the spacer 18 may be directly attached to the housing 11 to integrate the housing 11 and the cooling body 12.

Further, the number of semiconductor elements 17 installed on the mounting surface 12c of the cooling body 12 may be singular or three or more, and various shapes are adopted for the installation layout as long as they are surrounded by the spacer 18. You may.

Further, in the first embodiment, the heat insulating member 19 fills not all but a part of the mounting surface 12c of the cooling body 12 surrounded by the spacer 18 in the space where the semiconductor element 17 is not mounted. It may be provided in. However, it is advantageous that the space filled with the heat insulating member 19 is wide in that the heat insulating action can be obtained better.

Further, the opening 13a of the heat insulating partition wall 13 can be changed in various ways. For example, with respect to the four semiconductor elements 17, the two semiconductor elements 17 arranged side by side on the upper side in FIGS. 2 and 6 and the lower one. When the two semiconductor elements 17 arranged side by side on the left and right sides are divided into groups and viewed, an opening 13a may be formed so as to surround each group. Further, all four semiconductor elements 17 may be formed so as to fit in one opening 13a.

Further, in the second embodiment, the heat insulating cover 40 can be changed in various ways as long as it covers at least a part of the opening 13a of the heat insulating partition wall 13. For example, one opening 13a may have an area covered with the heat insulating cover 40 and an area not covered with the heat insulating cover 40. Further, when a plurality of openings 13a are formed, a heat insulating cover 40 may be provided for each opening 13a, and in this case, the heat insulating cover 40 for a part of the openings 13a may be omitted.

Further, in the second embodiment, each of the screw members 40 to 42 has various configurations such as a configuration provided with a hook and a fitting structure as long as each configuration is detachable as described above. Can be adopted.

Further, in the first embodiment, the screw member for attaching the spacer 18 to the cooling body 12 and the heat insulating partition wall 13 and the screw member for attaching the heat insulating partition wall 13 to the housing 11 are provided at different positions, and the heat is increased. The insulating partition 13 has electrical insulation performance. Therefore, also in the first embodiment, the insulation state between the cooling body 12 and the housing 11 can be ensured in the same manner as in the second embodiment.

10 Power converter 11 Housing 11b Opening 12 Cooler 12c Mounting surface 13 Thermal insulation partition 13a Opening 17 Semiconductor element 18 Spacer 19 Insulation member 26 Space 40 Insulation cover 41 First screw member (first fixing member)
42 Second screw member (second fixing member)

Claims (14)

With semiconductor elements
A cooling body having a mounting surface on which the semiconductor element is mounted and releasing heat of the semiconductor element,
A spacer provided on the mounting surface so as to surround the semiconductor element,
A power conversion device characterized by having a heat insulating member that fills a space in which the semiconductor element is not mounted among the mounting surfaces surrounded by the spacer. The power conversion device according to claim 1, wherein the cooling body is attached to a heat-insulated partition wall via the spacer. With more housing
The power conversion device according to claim 2 , wherein the heat-insulated partition wall closes an opening provided in the housing so that the cooling body is located outside the housing. The cooling body and the heat insulating partition wall are fixed by a first fixing member, and the heat insulating partition wall and the housing are fixed by a second fixing member.
The power conversion device according to claim 3 , wherein the first fixing member and the second fixing member are arranged at different positions in a plane direction orthogonal to the thickness direction of the heat insulating partition wall. .. The power conversion device according to any one of claims 2 to 4 , wherein the heat-insulated partition wall has an opening formed at least in a region corresponding to the semiconductor element. Further provided with a heat insulating cover covering at least a part of the opening.
The power conversion device according to claim 5 , wherein the heat insulating cover is detachably provided on the heat insulating partition wall. The power conversion device according to any one of claims 1 to 6 , wherein the spacer has a lower thermal conductivity than the constituent members of the cooling body. The power conversion device according to any one of claims 2 to 6 , further comprising a space surrounded by the spacer, the mounting surface, and the heat insulating partition wall. It has a space surrounded by the spacer, the mounting surface, and the heat insulating partition wall.
The power conversion device according to claim 3 or 4 , wherein the space constitutes a flow path through which outside air outside the housing can flow. A plurality of the semiconductor elements are mounted on the mounting surface,
The power conversion device according to any one of claims 1 to 9 , wherein the spacer is formed so as to surround the semiconductor element. A plurality of the semiconductor elements are mounted on the mounting surface,
The power conversion device according to any one of claims 1 to 9 , wherein the spacer is formed so as to surround the plurality of semiconductor elements in divided groups. A plurality of the semiconductor elements are mounted on the mounting surface,
The power conversion device according to any one of claims 1 to 9 , wherein the spacer is formed so as to surround the plurality of semiconductor elements. The cooling body is attached to the heat insulating partition via the spacer.
The cooling body is divided into a plurality of parts, and each of the divided cooling bodies is attached to one heat-insulated partition wall via the spacer according to any one of claims 10 to 12. The power converter described. The power conversion device according to claim 3 or 4 , wherein the semiconductor element as a whole is arranged outside the opening of the housing.

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