JP2021010200A - Electric circuit arrangement, power conversion device and manufacturing method of electric circuit arrangement - Google Patents

Abstract

To provide an electric circuit arrangement capable of suppressing deterioration of cooling performance even if a cover deforms due to pressure of cooling liquid.SOLUTION: An electric circuit arrangement 400 comprises interposing parts 350 which are installed by contacting opposite surfaces of upper and lower covers 340a and 340b that face heat radiation parts 330, and form flow paths with heat radiation bases 332. Fins 331 respectively have upper end faces 331T and side faces 331S. The interposing parts 350 have recesses 351 into which the upper end face 331T and part of the side face 331S near the upper end face 331T, of each fin 331, are inserted.SELECTED DRAWING: Figure 3

Description

The present invention relates to an electric circuit device, a power conversion device, and a method for manufacturing an electric circuit device.

Electric circuit devices such as power semiconductor modules incorporating power semiconductor elements that perform switching operations are widely used for consumer, in-vehicle, railway, substation equipment, etc. because of their high conversion efficiency. Since this electric circuit device generates heat when energized, the electric circuit device is required to have high heat dissipation. In particular, in in-vehicle applications, in order to cool an electric circuit device in order to reduce the size and weight, a highly efficient cooling system in which a cooling liquid such as water flows into a flow path formed in a flow path forming portion is adopted.
When the coolant is allowed to flow into the flow path of the flow path forming portion, the flow path forming portion may be deformed due to the hydraulic pressure and leak out of the flow path. If the coolant leaks, the flow rate of the coolant is reduced, resulting in reduced cooling performance. In order to prevent the coolant from leaking out of the flow path, for example, a second flow path forming member formed of an elastic body is housed inside the first flow path forming member, and the elastic body is expanded after mounting. A structure is known that fills the gap between the first flow path forming member and the second flow path forming member (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-166080

Patent Document 1 does not relate to an electric circuit device in which a flow path forming portion is deformed by the hydraulic pressure of a coolant.

The electric circuit device according to the first aspect of the present invention includes an electric circuit body having a semiconductor element and a conductor, a heat radiating base, a heat radiating portion having a plurality of fins, and the heat radiating base thermally coupled to the conductor, and the above. A cover of the heat radiating portion, which is provided on the opposite side of the electric circuit body so as to cover the heat radiating portion, is provided in contact with the facing surface of the cover facing the heat radiating portion, and flows between the heat radiating base. The fins include an interstitial portion forming a path, and the fins have an upper end surface and a side surface, respectively, and the interstitial portion is a vicinity of the upper end surface and the upper end surface of each of the fins. Has a recess into which a portion of the
In the method for manufacturing an electric circuit device according to the second aspect of the present invention, an electric circuit body having a semiconductor element and a conductor is prepared, and the heat dissipation base and the heat dissipation base of the heat dissipation part having a plurality of fins are attached to the conductor. Thermal coupling, providing a cover of the heat radiating portion on the opposite side of the electric circuit body to cover the heat radiating portion, and contacting the facing surface of the cover facing the heat radiating portion with the heat radiating base. The fins have an upper end surface and a side surface, respectively, including providing an interposition portion for forming a flow path between them, and providing the interposition portion means that the upper end surface of each of the fins is provided. And to form a recess in which a part of the side surface near the upper end surface is inserted.

According to the present invention, even if the cover is deformed by the pressure of the coolant, the decrease in cooling capacity can be suppressed.

FIG. 1 is a plan view of an embodiment of an electric circuit device according to the present invention. FIG. 2 is a sectional view taken along line II-II of the electric circuit apparatus shown in FIG. FIG. 3 is a sectional view taken along line III-III of the electric circuit apparatus illustrated in FIG. FIG. 4 is an external perspective view showing an example of the power module shown in FIG. FIG. 5 is a circuit diagram showing an example of the circuit of the power module shown in FIG. FIG. 6 is an exploded perspective view for showing a method of manufacturing the electric circuit device shown in FIG. FIG. 7 is a perspective view for showing a method of manufacturing an electric circuit device following FIG. FIG. 8 is a perspective view for showing a method of manufacturing an electric circuit device following FIG. 9 (a) to 9 (c) are enlarged cross-sectional views of each step showing a method of manufacturing an electric circuit device when the interlayer portion of FIG. 2 is a non-woven fabric. 10 (a) to 10 (c) are enlarged cross-sectional views of each step showing a method of manufacturing an electric circuit device when the interposition portion of FIG. 2 is a paste or a cured resin product. 11 (a) to 11 (d) are enlarged cross-sectional views illustrating a modified example of the fin shown in FIG. 2, respectively. FIG. 12 is a sectional view taken along line II-II of the electric circuit apparatus shown in FIG. 1, FIG. 12 (a) shows a state in which cooling water is not flowing, and FIG. 12 (b) shows a state in which cooling water is flowing. The flowing state is shown, and FIG. 12 (c) is an enlarged view of the region XIIc of FIG. 12 (b). 13 is a sectional view taken along line III-III of the electric circuit apparatus illustrated in FIG. 1, FIG. 13 (a) shows a state in which cooling water is not flowing, and FIG. 13 (b) shows a state in which cooling water is flowing. The flowing state is shown, and FIG. 13 (c) is an enlarged view of the region XIIIc of FIG. 13 (b). 14A and 14B are cross-sectional views of an electric circuit device of a comparative example, FIG. 14A shows a state in which cooling water is not flowing, and FIG. 14B shows a state in which cooling water is flowing. 15A and 15B are cross-sectional views showing a modified example of the manufacturing method of the electric circuit device of the present invention, FIG. 15A shows before assembly, and FIG. 15B shows after assembly. FIG. 16 is a circuit diagram of a power conversion device using the electric circuit device according to the present invention. FIG. 17 is an external perspective view showing an example of the power conversion device shown in FIG. FIG. 18 is a sectional view taken along line XVIII-XVIII of the power converter shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and are appropriately omitted and simplified for clarification of the description. The present invention can also be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.
The position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc., in order to facilitate understanding of the invention. Therefore, the present invention is not necessarily limited to the position, size, shape, range and the like disclosed in the drawings.

FIG. 1 is a plan view of an embodiment of an electric circuit device according to the present invention, FIG. 2 is a sectional view taken along line II-II of the electric circuit device shown in FIG. 1, and FIG. 3 is shown in FIG. FIG. 3 is a sectional view taken along line III-III of the illustrated electric circuit device.
As shown in FIGS. 1 to 3, the electric circuit device 400 has an upper cover 340a and a lower cover 340b, and has an elongated rectangular parallelepiped shape. The upper and lower covers 340a and 340b are made of iron, an aluminum alloy, or the like.

The electric circuit device 400 includes a module structure 370 in which three power modules (electric circuit bodies) 300 are arranged between a pair of upper and lower module connecting members 341U and L, and a housing 340 that houses the module structure 370. I have. The module structure 370 is cooled by the coolant flowing in the housing 340. The module configuration 370 includes three power modules 300 and a pair of upper and lower module connecting members 341U and L arranged on the upper and lower surfaces of the three power modules 300. Each power module 300 is fixed to the fixing portions 341a of the module connecting members 341U and L at the peripheral edge of the heat dissipation base 332. The heat dissipation base 332 and the module connecting members 341U and L may be fixed by welding such as laser welding as shown in FIG. 2, or by a fastening member (not shown). At the upper and lower ends of the module connecting members 341U and 341L, openings 341k through which the coolant passes are provided.

The upper cover 340a and the lower cover 340b are fixed to both end portions 341b of the module connecting members 341U and L by welding such as laser welding or fastening members (not shown). A pair of left and right flow path connecting members 345 provided with upper and lower through holes 345a are interposed between both ends 341b of the module connecting members 341U and 341L to which the upper and lower covers 340a and 340b are fixed. The upper / lower covers 340a and 340b and the pair of left and right flow path connecting members 345 form the flow path forming body 340. An upper flow path 501 is formed between the three power modules 300, that is, the module configuration 370 and the upper cover 340a, and a lower flow path 502 is formed between the three power modules 300 and the lower cover 340b. ing. The flow path connecting member 345 has an upper and lower through hole 345a that communicates the upstream flow path 501 and the downstream flow path 502 inside.

Each power module 300 has an electric circuit body 310, a heat radiating unit 330, and a sealing resin 360. The heat radiating unit 330 has a plurality of pin-shaped fins 331 and a heat radiating base 332. The electric circuit body 310 includes a plurality of semiconductor elements 150, and first to fourth conductors 410 to 413 (however, 413 is not shown in FIGS. 2 and 3, but is shown in FIG. 5). It has an emitter-side wiring board 422 and a collector-side wiring board 423.

The upper flow path 501 and the lower flow path 502 are communicated with each other by the upper and lower through holes 345a of the flow path connecting member 345. The lower cover 340b is provided with an inflow port 503 into which the coolant flows in and an outflow port 504 in which the coolant flows out. The coolant flowing in from the inflow port 503 flows in the lower flow path 502, flows between the fins 331 of the heat radiating portion 330 on the lower side, and cools the power module 300. Further, the coolant flowing in from the inflow port 503 cools the lower part, flows into the upper flow path 501 through the upper and lower through holes 345a, flows between the fins 331 of the heat radiating portion 330 on the upper side, and flows through the power module 300. To cool.

On the lateral side surface of the module configuration 370 in the lateral direction, the coolant flows from the right end surface of the module configuration 370 in FIG. 2 between the fins 331, and flows between the fins 331 on the left end surface of the module configuration 37070. Out of the road. A flow path through which the coolant flows is not formed on the outside of the side surface in the lateral direction.

As shown in FIG. 5, each power module 300 has a 2in1 structure having an upper arm circuit 305a and a lower arm circuit 305b. The electric circuit device 400 of this embodiment has three power modules 300. Therefore, the electric circuit device 400 of this embodiment is a 6in1 package.

FIG. 4 is an external perspective view of an example of the power module shown in FIG.
The power module 300 includes a module main body 301 which is a resin package in which internal electronic components are sealed with a sealing resin 360, a plurality of power terminals 315B, 319B and 320B for inputting and outputting a large current, and a plurality of signals for inputting and outputting signals. It has terminals 325C, M, K, L, S, and U. The module body 301 has a substantially rectangular parallelepiped shape. The plurality of power terminals 315B, 319B and 320B and the plurality of signal terminals 325C, M, K, L, S and U project from one side 301a of the module main body 301 and the other side 301b facing the one side. A heat radiating portion 330 including a large number of fins 331 and a heat radiating base 332 is provided on each of the main surface 302 side of the module main body 301 and the back surface 303 side which is the facing surface of the main surface 302.

Power terminals such as the positive electrode side terminal 315B and the negative electrode side terminal 319B project from the other side 301b of the module main body 301. An AC side terminal 320B protrudes from one side 301a of the module main body 301 as a power terminal.
The signal terminals of the lower arm gate signal terminal 325L, the mirror emitter signal terminal 325M, the Kelvin emitter signal terminal 325K, and the collector sense signal terminal 325C project from the other side 301b of the module main body 301. Signal terminals such as an upper arm gate signal terminal 325U, a temperature sense signal terminal 325S, a mirror emitter signal terminal 325M, a Kelvin emitter signal terminal 325K, and a collector sense signal terminal 325C project from one side 301a of the module main body 301.

FIG. 5 is a circuit diagram showing an example of the circuit of the power module shown in FIG.
The power module 300 includes an upper arm circuit 305a having a switching function including an active element 155 and a diode 156, and a lower arm circuit 305b having a switching function including an active element 157 and a diode 158. Transistors such as IGBTs (Insulated Gate Bipolar Transistors) and MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) are used as the active elements 155 and 157. As the diodes 156 and 158, SBD (Schottky Diode), FRD (Fast Recovery Diode) and the like are used. Si is often used as the material constituting the semiconductor element, but SiC, GaN, GaO and the like can also be used.

As shown in FIG. 5, the positive electrode side terminal 315B is connected to the third conductor 412. The collector electrode of the active element 155 and the cathode electrode of the diode 156 constituting the switching element of the upper arm circuit are electrically connected by the third conductor 412. The emitter electrode of the active element 155 and the anode electrode of the diode 156 are electrically connected by the second conductor 411.

The negative electrode side terminal 319B is electrically connected to the fourth conductor 413. The emitter electrode of the active element 157 and the anode electrode of the diode 158 constituting the switching element of the lower arm circuit are electrically connected by the fourth conductor 413. The collector electrode of the active element 157 and the cathode electrode of the diode 158 are electrically connected by the first conductor 410. The first conductor 410 and the second conductor 411 are electrically connected via the intermediate electrode 414. The AC side terminal 320B is electrically connected to the first conductor 410. The Kelvin emitter signal terminal 325K is connected to the emitter electrode of each of the upper arm circuit and the lower arm circuit. The collector sense signal terminal 325C of the upper arm circuit is electrically connected to the third conductor 412, and the collector sense signal terminal 325C of the lower arm circuit is connected to the first conductor 410.
In the following, the active element 155, 157 and the diode 156, 158 will be described as the semiconductor element 150.

With reference to FIGS. 2 and 3, a collector-side wiring board 423 is interposed between the third conductor 412 and the heat dissipation base 332 on the lower side. The semiconductor element 150 and the third conductor 412, the third conductor 412 and the collector side wiring board 423, and the collector side wiring board 423 and the lower heat dissipation base 332 are joined by a metal joining member 51 such as solder or sintered metal, respectively. Has been done.

An emitter-side wiring board 422 is interposed between the second conductor 411 and the heat dissipation base 332 on the upper side. The semiconductor element 150 and the second conductor 411, the second conductor 411 and the emitter-side wiring board 422, and the emitter-side wiring board 422 and the heat dissipation base 332 on the upper side are joined by metal joining members such as solder and sintered metal, respectively. ing. Therefore, the heat dissipation base 332 on the lower side and the third conductor 412 are thermally conductively coupled, in other words, thermally coupled. Further, the heat dissipation base 332 on the upper side and the second conductor 411 are thermally conductively coupled, in other words, thermally coupled.

The space between the upper and lower heat dissipation bases 332 is sealed with a sealing resin 360. The sealing resin 360 is formed by, for example, molding such as a transfer mold.

A circuit pattern (not shown) is formed on the emitter-side wiring board 422 and the collector-side wiring board 423. By using the wiring board on which the pattern is formed, there is an advantage that the alignment of the second conductor 411 which is the emitter side conductor and the third conductor 412 which is the collector side conductor becomes easy. Further, by providing the thick conductors 410 to 414 on the semiconductor element 150 side of each of the emitter side wiring board 422 and the collector side wiring board 423, the heat of the semiconductor element 150 can be diffused and the heat dissipation can be improved. .. The electric circuit device 400 can be applied to a power conversion device that inputs and outputs a three-phase alternating current. By forming the electric circuit device 400 into a 6in1 package in which three power modules 300 incorporating the upper and lower arm circuits 105a and 105b are connected, it becomes easy to assemble when the electric circuit device 400 is used as a power conversion device.

As described above, the upper / lower covers 340a and 340b and the two flow path connecting members 345 form a flow path forming body 340 through which a cooling liquid such as water flows. Flow path connecting members 345 are provided at both ends in the longitudinal direction (left and right ends in FIG. 2) of the module configuration 370, and the sealing resins 360 at both left and right ends are covered with the flow path connecting members 345, and the sealing resin 360. Is isolated from the coolant. Therefore, the sealing resin 360 is immersed in the coolant and swells to prevent the coolant from entering the vicinity of the semiconductor element 150. Since the upper and lower flow paths 501 and 502 are communicated with each other through the upper and lower through holes 345a of the flow path connecting member 345, the cooling liquid can flow in the upper flow path 501 and the lower flow path 502 in parallel. .. Therefore, the pressure loss of the coolant can be reduced, and the output of the motor that circulates the coolant can be reduced.

As shown in FIGS. 2 and 3, an interposition portion 350 is provided between the upper cover 340a and the heat radiating portion 330 on the upper side, and between the lower cover 340b and the heat radiating portion 330 on the lower side. ing. The interposition portion 350 has a function of suppressing a reduction in the flow rate of the coolant flowing between the fins 331 in the upper flow path 501 and between the fins 331 in the lower flow path 502. The interposition portion 350 will be described in detail later.
Since the interposition portion 350 is the same on the upper cover 340a side and the lower cover 340b side, the upper cover 340a side will be described as a representative below.

The interposing portion 350 is in contact with the inner surface of the upper cover 340a, in other words, the surface on the heat radiating portion 330 side. The interposition portion 350 is formed with recesses 351 (see also FIGS. 9 (c) and 10 (c)) into which the upper side of each fin 331 of the heat radiating portion 330 is inserted. The side surface 351S of the recess 351 (see also FIGS. 9 (c) and 10 (c)) is in contact with the outer peripheral side surface on the upper side of the fin 331. When the coolant flows into the upper flow path 501 and flows between the fins 331, the upper cover 340a warps due to the hydraulic pressure of the coolant so that the central portion is lifted upward with respect to the side edge portion (FIG. 12 (FIG. 12). b), see FIG. 13 (b)). In this state, each fin 331 is inserted to a depth that holds a state in which a part of the upper side is inserted into the recess 351 of the interposition portion 350. That is, while the coolant is flowing in the upper flow path 501, a part of the outer peripheral side surface of each fin 331 on the upper side is in contact with the side surface 351S of the recess 351 of the interposition portion 350. Therefore, the coolant flowing between the fins 331 does not flow above the upper end surface 331T of the fins 331 (see FIGS. 12 (b) and 13 (b)). That is, the reduction in the flow rate of the coolant flowing between the fins 331 is suppressed. As a result, it is possible to suppress a decrease in heat dissipation performance.
It should be noted that this function will be specifically described below together with examples.

A non-woven fabric, a paste material, a cured resin product, or the like can be used for the interposing portion 350. When a non-woven fabric is used, the fiber length of the non-woven fabric is preferably 5 times or more the thickness in the region where the recess 351 is not provided. If the fiber length of the non-woven fabric is smaller than 5 times the thickness of the interposition portion 350, the entanglement of the non-woven fabric is insufficient, and the pressure of the coolant increases the possibility that the fibers will fall off partially or comprehensively. is there. The non-woven fabric can be used as a single layer, but in order to prevent the fibers from falling off while increasing the deformability, a laminated structure of a densely formed non-woven fabric and a sparsely formed non-woven fabric may be used. When the densely formed non-woven fabric is provided on the side in contact with the coolant, the effect of suppressing the falling off of the fibers is improved.

A sheet-like film may be used instead of the densely formed non-woven fabric. The material of the non-woven fabric should be selected according to the type of coolant, but when using an aqueous coolant, it is desirable to use polyethylene or polypropylene, which has high water resistance and low cost. Of the two, polypropylene having high heat resistance is preferable.
When an oil system is used as the coolant, it is preferable to use a material having high resistance to the oil system such as cellulose and polyethylene terephthalate.

When the interposition portion 350 is formed of a non-woven fabric, the interposition portion 350 is arranged between the cover 340a and the fins 331 when the flow path forming body 340 and the module component 370 are assembled. For example, the upper and lower interposition portions 350 are fixed to the upper and lower covers 340a and 340b, face the upper and lower fins 331 of the module configuration 370, and each fin 331 is inserted into the recess 351 of the interposition portion 350. Then, when the flow path forming body 340 and the module component 370 are assembled, the bottom surface of the recess 351 of the interposing portion 350 is pressed by the upper end surface 331T of each fin 331, and the interposing portion 350 is pressed against the inner surface of the upper cover 340a. Contact. This manufacturing method will be specifically described later with reference to FIGS. 6 to 8.

When the interposition portion 350 is formed of a paste material, it is preferable to use one having a high viscosity in order to suppress deformation due to the hydraulic pressure and gravity of the coolant. High viscosity means that the storage viscosity measured in an oscillation mode with a frequency of 10 Hz using a parallel plate sensor with a gap of 1 mmφ and 20 mm is 500 Pa · s or more. If the viscosity is less than 500 Pa · s, it will be deformed by hydraulic pressure and gravity, and there is a possibility that the cooling performance will be reduced by more than 10% during the 15-year usage period. As the paste material, a paste material having a high viscosity can be used at the initial stage, but a paste material which is thickened by two-component mixing, humidity, heat or the like to increase the viscosity is preferable because of its excellent productivity. When the interposing portion 350 is formed of a paste material, the interposing portion 350 can be adhered to the upper cover 340a in advance by the adhesive force of the interposing portion 350 itself, so that the productivity can be improved. it can.
The material of the paste material is not particularly limited as long as it is a material having high resistance to the coolant, but when an aqueous coolant is used, a silicone-based material having high water resistance is preferable.

When the intermediate portion 350 is formed by using a cured resin product, the resin before curing is pressed by the upper end surface 331T of the fins 331 to form a recess 351 and then cured by curing the resin. Can be done. As the curing reaction, a two-component mixture, humidity, heat, or the like can be used. Further, the productivity can be improved by fixing the resin composition before curing to the upper cover 340a in advance. The material of the cured resin product is not particularly limited as long as it is a material having high resistance to the coolant, but when an aqueous coolant is used, a silicone-based material having high water resistance is preferable.

FIG. 6 is an exploded perspective view for showing the manufacturing method of the electric circuit device shown in FIG. 1, and FIG. 7 is a perspective view for showing the manufacturing method of the electric circuit device following FIG. 8 is a perspective view for showing a method of manufacturing an electric circuit device following FIG. 7.
The three power modules 300 are integrated by a module connecting member 341 to form a module component 370. The upper cover 340a is arranged above the module configuration 370, and the lower cover 340b is arranged below the module configuration 370.
An interposition portion 350 is arranged on the inner surfaces of the upper cover 340a and the lower cover 340b, that is, on the surfaces facing the module configuration 370. The upper end surfaces 331T of the fins 331 of each power module 300 are arranged so as to face the interposition portion 350.

As shown in FIG. 7, each of the upper cover 340a and the lower cover 340b is fastened to and fixed to the module configuration 370 by a fastening member (not shown). As a result, the upper end surface 331T of each fin 331 bites into the interposition portion 350 fixed to the inner surfaces of the upper cover 340a and the lower cover 340b, respectively. The upper end surface 331T of each fin 331 bites into the interposing portion 350 by a preset depth to deform the interposing portion 350. Therefore, the interposition portion 350 is formed with a recess 351 having a depth in which each fin 331 bites.
Therefore, after that, if the upper cover 340a and the lower cover 340b are removed from the module configuration 370, as shown in FIG. 8, the interposition portions 350 fixed to the upper cover 340a and the lower cover 340b have fins. The recess 351 formed by 331 remains.

9 (a) to 9 (c) are enlarged cross-sectional views of each step showing a method of manufacturing an electric circuit device when the interlayer portion of FIG. 2 is a non-woven fabric.
The fin 331 formed in the heat radiating portion 330 has an upper end surface 331T and a side surface 331S.
As shown in FIG. 9A, each fin 331 has an upper end surface 331T arranged so as to face an interposition portion 350A formed of a non-woven fabric.
In the following, the upper cover 340a and the lower cover 340b may be referred to as a flow path forming body 340.

By pressing the upper end surface 331T of the fin 331 of the heat radiating portion 330 against the interposing portion 350A, the region of the interposing portion 350A sandwiched between the flow path forming body 340 and the upper end surface 331T of the fin 331 is compressed. Since the interposition portion 350A is made of a non-woven fabric, the entanglement of the fibers becomes dense in the compressed region, and the entanglement of the fibers hardly changes in the uncompressed region. That is, a step portion is formed at the boundary between the compressed region and the uncompressed region of the non-woven fabric, and the uncompressed region protrudes from the compressed region. The side surface 331S of the fin 331 comes into contact with the uncompressed region of the non-woven fabric. That is, a side contact portion 331SC in contact with the side surface of the non-compressed region of the non-woven fabric is formed on the side surface 331S of the fin 331. This state is illustrated in FIG. 9 (b).

A deformation in which the fibers are dense in the compressed region of the non-woven fabric and the entanglement of the fibers hardly changes in the non-compressed region of the non-woven fabric is an irreversible deformation that hardly recovers even when the load is released. Therefore, as shown in FIG. 9C, even if the fin 331 is separated from the interposition portion 350A, the shape is maintained almost as it is.
When the interposition portion 350 has an elastic force that restores after being deformed, when the upper end surface 331T of the fin 331 is pressed against the bottom surface of the recess 351 of the interposition portion 350, the interposition portion 350 Due to the restoring force of 350, the reaction force of the pressing force applied to the upper end surface 331T of the fin 331 acts on the flow path forming body 340. Therefore, the flow path forming body 340 is warped so that the central portion side protrudes.

On the other hand, when the interposing portion 350 is formed of a material or structure that deforms irreversibly, even if the interposing portion 350 is deformed to form the recess 351 and then the load is released, the interposing portion 350 is provided. No reaction force is generated on the upper end surface 331T of the fin 331 when the portion 350 is deformed. Therefore, it is possible to prevent the flow path forming body 340 from being warped due to the reaction force of the interposing portion 350. As a result, it becomes possible to use a flow path forming body 340 having low rigidity, and it is possible to make the material of the flow path forming body 340 low in rigidity or to reduce the thickness.
In addition, in this specification, it is referred to as an irreversible structure including an irreversible material and structure.

10 (a) to 10 (c) are enlarged cross-sectional views of each step showing a method of manufacturing an electric circuit device when the interposition portion of FIG. 2 is a paste or a cured resin product.
As shown in FIG. 10A, each fin 331 has an upper end surface 331T arranged so as to face an interposition portion 350B formed of a paste or a cured resin product.
By pressing the upper end surface 331T of the fin 331 of the heat radiating portion 330 against the interposing portion 350B, the region of the interposing portion 350B sandwiched between the flow path forming body 340 and the upper end surface 331T of the fin 331 is pressed. Since the interposition portion 350B is formed of the paste or the cured resin product, the paste or the cured resin product in the pressed region is extruded to the periphery.

On the other hand, in the region not pressed by the upper end surface 331T of the fin 331, the extruded paste or the cured resin product before curing flows, so that the region near the side surface 331S of the fin 331 slightly protrudes from the surface, but the whole There is almost no change as. That is, the recess 351 is formed in the interposition portion 350B by pressing, and the circumference of the recess 351 remains almost the original thickness. Therefore, a side contact portion 331SC in contact with the interposition portion 350B formed of the paste or the cured resin product before curing is formed on the side surface 331S of the fin 331. This state is illustrated in FIG. 10 (b).

When the curing of the resin before curing is advanced from this state, the state of FIG. 10B is maintained in the interposition portion 350B formed of the paste or the cured resin product. The deformation of the paste or the cured resin product forming the interposition portion 350B is irreversible as in the case of the non-woven fabric. Therefore, as shown in FIG. 10C, even if the fin 331 is separated from the interposition portion 350B, the shape is maintained almost as it is. By holding the irreversible deformation of the interposition portion 350B, once the interposition portion 350B is deformed during the process, the deformed shape can be retained even if the rigidity of the flow path forming body 340 is low. It becomes.

As described above, in the present embodiment, the interposition portion 350 has an irreversible deformation structure. Therefore, it is possible to suppress the occurrence of warpage in the flow path forming body 340.
The irreversible deformation includes a deformation that is not restored at all by the deformation and a deformation that is restored to some extent.

11 (a) to 11 (d) are enlarged cross-sectional views for explaining a modified example of the fin shown in FIG. 2, respectively.
The fin 331A of the modified example 1 shown in FIG. 11A has a chamfered 381 formed on the upper end surface 331T. The chamfer 381 is an inclined surface or an arcuate curved surface. When the chamfered portion 381 of the fin 331A of the modification 1 is less than 0.1C, it is preferable that the side surface 351S of the recess 351 of the interposition portion 350 comes into contact with the chamfered portion 381 and the side surface 331S in the vicinity of the chamfered portion 381. .. When the chamfered portion 381 of the fin 331A of the modification 1 is 0.1C or more, the side surface 351S of the recess 351 of the interposing portion 350C contacts only the chamfered portion 381 of the fin 331A, and the side surface of the fin 331A near the chamfered portion 381. It does not have to reach 331S.
The chamfered portion 381 of the fin 331A in the present embodiment is included in the side surface 331S of the fin 331A.
It is preferable that the side surface 351S (see FIGS. 9C and 10C) of the recess 351 of the interposition portion 350 comes into contact with a part of the fin 331A near the upper end surface 331T of the side surface 331S.

The fin 331B of the second modification illustrated in FIG. 11B has a long inclined surface 382 extending from the upper end surface 331T to the side surface 331S. With respect to the fin 331B of the second modification, the side surface 351S of the recess 351 of the interposition portion 350 is adjacent only to the vicinity of the upper end surface 331T of the inclined surface 382 of the fin 331B, in other words, the upper end surface 331T of the inclined surface 382. The configuration may be such that it contacts only the region.
The inclined surface 382 of the fin 331B in the present embodiment is included in the side surface 331S of the fin 331B.
It is preferable that the side surface 351S (see FIGS. 9C and 10C) of the recess 351 of the interposition portion 350 comes into contact with a part of the fin 331B near the upper end surface 331T of the side surface 331S.

A dome-shaped curved curved surface 383 is formed on the upper end surface 331T of the fin 331C of the modified example 3 shown in FIG. 11 (c). The upper end surface 331T of the fin 331C is located at the center of the curved surface 383 of the fin 331. This position is the center position of the surface of the fin 331C in a plan view. With respect to the fin 331C of the third modification, the side surface 351S of the recess 351 of the interposition portion 350 is only near the upper end surface 331T of the curved surface 383 of the fin 331C, in other words, the upper end surface 331T of the dome-shaped curved surface 383. The configuration may be such that only the region adjacent to the dome is in contact with the dome.
The curved surface 383 of the fin 331C in the present embodiment is included in the side surface 331S of the fin 331C.
It is preferable that the side surface 351S (see FIGS. 9C and 10C) of the recess 351 of the interposition portion 350 comes into contact with a part of the fin 331C near the upper end surface 331T of the side surface 331S.

The fin 331D of the modified example 4 illustrated in FIG. 11D has a conical shape. In other words, the upper end surface 331T of the fin 331D is the apex of the cone, and the side surface 331S other than the upper end surface 331T which is the apex. The upper end surface 331T of the fin 331 of the modified example 4 is located on the central axis of the fin 331.
In the present embodiment, the side surface 351S (see FIGS. 9C and 10C) of the recess 351 of the interposition portion 350 contacts a part of the fin 331D near the upper end surface 331T of the side surface 331S. It is preferable to do so.

[Example]
FIG. 12 is a sectional view taken along line II-II of the electric circuit apparatus shown in FIG. 1, FIG. 12 (a) shows a state in which cooling water is not flowing, and FIG. 12 (b) shows a state in which cooling water is flowing. The flowing state is shown, and FIG. 12 (c) is an enlarged view of the region XIIc of FIG. 12 (b). 13 is a sectional view taken along line III-III of the electric circuit apparatus illustrated in FIG. 1, FIG. 13 (a) shows a state in which cooling water is not flowing, and FIG. 13 (b) shows a state in which cooling water is flowing. The flowing state is shown, and FIG. 13 (c) is an enlarged view of the region XIIIc of FIG. 13 (b).
An electric circuit device 400 having the structure shown in FIGS. 1 to 3 was manufactured.
The flow path forming body 340 was made of aluminum having a thickness of 1.5 mm. The interposition portion 350 was formed of a non-woven fabric. Water was used as the coolant and flowed into the upper and lower flow paths 501 and 502. The water pressure of the cooling water was 0.3 MPa. Before supplying the cooling water to the electric circuit device 400, the upper and lower covers 340a and 340b were flat as a whole, as shown in FIGS. 12A and 13A. That is, no warpage was observed.

Cooling water was flowed through the upper and lower flow paths 501 and 502 of the electric circuit device 400 at the above water pressure. As a result, as shown in FIGS. 12 (b) and 13 (b), the upper and lower covers 340a and 340b each had a warp in which the central portion protruded to the opposite side to the module configuration 370. At this time, as shown in FIGS. 12 (c) and 13 (c), the side contact portion 351SC of the recess 351 of the interposition portion 350 was in contact with the side surface 331S near the upper end surface 331T of the fin 331. .. When the heat dissipation of the electric circuit device 400 of this embodiment was compared with that of a reference electric circuit device having a large rigidity in which the flow path forming body 340 does not warp, the decrease in heat dissipation was suppressed to 1% or less.
As described above, according to the present embodiment, it is confirmed that it is possible to suppress the deterioration of heat dissipation performance even if the thickness is formed to have a small rigidity so as to cause warpage caused by the hydraulic pressure of the coolant. I was able to.

[Comparison example]
14A and 14B are cross-sectional views of an electric circuit device 400R of a comparative example, FIG. 14A shows a state in which cooling water is not flowing, and FIG. 14B shows a state in which cooling water is flowing. ..
An electric circuit device 400R of a comparative example was manufactured.
In the electric circuit device 400R of the comparative example, the interposition portion 350r was formed of a rubber sheet. Other than this, the same as in the examples, the flow path forming body 340 was made of aluminum having a thickness of 1.5 mm.
As shown in FIG. 14B, in the electric circuit device 400R of the comparative example, in the state where the coolant is flowing, the upper and lower covers 340a and 340b have the central portion protruding to the opposite side to the module configuration 370. As shown above, the warp was large, and the upper and lower covers 340a and 340b were deformed by about 1 mm, respectively. Therefore, a gap C _c is generated between the interposition portion 350r and the upper end surface 331T of the fin 331, and in addition to the flow path flowing between the fins 331, a bypass flow flowing between the interposition portion 350r and the upper end surface 331T of the fin 331. f _c has occurred. As a result, in the electric circuit device 400R of the comparative example, the heat dissipation property was reduced by 15% as compared with the standard electric circuit device having a large rigidity in which the flow path forming body 340 does not warp.

As described above, according to the present embodiment, the warp of the flow path forming body 340 such as the upper / lower covers 340a and 340b can be reduced by forming the interposition portion 350 irreversibly with respect to the deformation. .. Therefore, it was confirmed that even if the flow path forming bodies 340 such as the upper and lower covers 340a and 340b are formed to have a thickness with low rigidity, it is possible to suppress the deterioration of heat dissipation performance. ..

(Modification example)
15A and 15B are cross-sectional views showing a modified example of the manufacturing method of the electric circuit device of the present invention, FIG. 15A shows before assembly, and FIG. 15B shows after assembly.
In the electric circuit device 400 shown in FIG. 15, the interposition portion 350 is made of a non-woven fabric.
As shown in FIG. 15A, the interposition portion 350 is wound or folded at both ends to form a thick portion 372. Each thick portion 372 of the interposition portion 350 is fitted into grooves 371 provided at both ends in the longitudinal direction of the module configuration 370. The interposition portion 350 is similarly attached to both the front and back sides of the module configuration 370.

The flow path forming body 340 is configured by connecting the upper and lower covers 340a and 340b with a flow path connecting member 345. A chamfered portion 375a is formed in one opening 375 of the flow path forming body 340.
As shown in FIG. 15A, one side end of the module configuration 370 to which the interposition portions 350 are attached to both the front and back surfaces is arranged so as to face the opening 375 of the flow path forming body 340, and arrows. Push down in the X direction.

As shown in FIG. 15B, by pushing down the module configuration 370 to which the interposition portions 350 are attached to both the front and back surfaces in the direction of arrow X, the module configuration 370 flows along with the interposition portion 350. It is housed in the form 340. The distance between the upper and lower covers 340a and 340b constituting the flow path forming body 340 is set so that the upper end surface 331T of the fin 331 is inserted into the interposition portion 350 at a preset depth. Therefore, each of the fins 331 provided in the module configuration 370 presses the interposition portion 350 with the upper end surface 331T, and the vicinity of the upper end surface 331T of the fin 331 and the upper end surface 331T of the side surface 331S is inserted into the interposition portion 350. Will be done.
According to the electric circuit device 400 of the modified example, the step of fixing the interposition portion 350 to the flow path forming body 340 can be omitted.

According to this embodiment, the following effects are obtained.
(1) The electric circuit device 400 has a power module (electric circuit body) 300 having a semiconductor element 150 and first to fourth conductors 410 to 413, a heat dissipation base 332 and a plurality of fins 331, and the heat dissipation base 332 has a heat dissipation base 332. The heat radiating unit 330 thermally coupled to the first to fourth conductors 410 to 413, and the upper and lower covers 340a and 340b provided on the opposite side of the power module 300 of the heat radiating unit 330 so as to cover the heat radiating unit 330. The lower covers 340a and 340b are provided in contact with the facing surface facing the heat radiating portion 330, and are provided with an interposing portion 350 that forms a flow path with the heat radiating base 332. The fins 331 have an upper end surface 331T and a side surface 331S, respectively, and the interposition portion 350 has a recess 351 into which a part of the upper end surface 331T and the side surface 331S near the upper end surface 331T of each of the fins 331 is inserted. Have. Therefore, the reduction in the flow rate of the coolant flowing between the fins 331 can be suppressed, and the reduction in the heat dissipation performance of the electric circuit device 400 can be suppressed.

(2) The side surface 351S of the recess 351 of the interposition portion 350 is in contact with a part of the side surface 331S of the fin 331 near the upper end surface 331T. Therefore, it is possible to suppress the formation of a coolant bypass flow path between the upper / lower covers 340a and 340b and the upper end surface 331T of the fins 331, further reducing the thermal performance of the electric circuit device 400. , Can be suppressed.

The interposition portion 350 has a structure in which deformation is irreversible. Therefore, in a state where the upper end surface 331T of the fin 331 is in contact with the bottom surface of the recess 351 of the interposing portion 350, deformation of the upper and lower covers 340a and 340b due to the reaction force of the interposing portion 350 can be suppressed. Further, since the deformation of the upper / lower covers 340a and 340b can be suppressed, the upper / lower covers 340a and 340b have low rigidity, for example, the thickness of the upper / lower covers 340a and 340b can be reduced or the cost is low. It can be formed from various metal materials.

Nonwoven fabrics, paste materials, and cured resin products are suitable for making the deformation of the interposition portion 350 irreversible.

(3) The interposing portion 350 is fixed to the facing surface of the upper / lower covers 340a and 340b facing the heat radiating portion 330. Therefore, the electric circuit device 400 can be easily assembled.

(4) In a state where the upper and lower covers 340a and 340b are deformed by the pressure of the coolant flowing in the flow path, the bottom surface of the recess 351 of the interposition portion 350 is separated from the upper end surface 331T of each fin 331. , A part of the upper part of each fin 331 is inserted into the recess 351. The present invention uses members having low rigidity as the upper and lower covers 340a and 340b, and even for a structure in which the bottom surface of the recess 351 of the interposition portion 350 is separated from the upper end surface 331T of each fin 331, the electric circuit device 400 It is possible to suppress the reduction of heat dissipation performance.

FIG. 16 is a circuit diagram of a power conversion device using the electric circuit device according to the present invention.
The power conversion device 200 includes inverter circuit units 140 and 142, an inverter circuit unit 43 for auxiliary equipment, and a capacitor module 500. The inverter circuit units 140 and 142 include a plurality of power modules 300, and connect them to form a three-phase bridge circuit. When the current capacity is large, the power modules 300 are further connected in parallel, and these parallel connections are made corresponding to each phase of the three-phase inverter circuit to cope with the increase in the current capacity. Further, the increase in current capacity can be coped with by connecting the active elements 155, 157 and the diodes 156, 158, which are power semiconductor elements built in the power module 300, in parallel.

The inverter circuit unit 140 and the inverter circuit unit 142 have the same basic circuit configuration, and basically the same control method and operation. Since the outline of the circuit-like operation of the inverter circuit unit 140 and the like is well known, detailed description thereof will be omitted here.
As described above, the upper arm circuit includes an active element 155 for the upper arm and a diode 156 for the upper arm as a power semiconductor element for switching, and the lower arm circuit is a lower power semiconductor element for switching. It includes an active element 157 for the arm and a diode 158 for the lower arm. The active elements 155 and 157 receive a drive signal output from one or the other of the two driver circuits constituting the driver circuit 174 and perform a switching operation to convert the DC power supplied from the battery 136 into three-phase AC power. ..

As described above, the active element 155 for the upper arm and the active element 157 for the lower arm include a collector electrode, an emitter electrode, and a gate electrode. The diode 156 for the upper arm and the diode 158 for the lower arm include two electrodes, a cathode electrode and an anode electrode. As shown in FIG. 3, the cathode electrode of the diode 156 and 158 is electrically connected to the collector electrode of the IGBT 155 and 157, and the anode electrode is electrically connected to the emitter electrode of the active element 155 and 157. As a result, the current flow from the emitter electrode of the active element 155 for the upper arm and the active element 157 for the lower arm to the collector electrode is in the forward direction.
A MOSFET (metal oxide semiconductor type field effect transistor) may be used as the active element. In this case, the diode 156 for the upper arm and the diode 158 for the lower arm are unnecessary.

The positive electrode side terminal 315B and the negative electrode side terminal 319B of each of the upper and lower arm series circuits are connected to the DC terminals for connecting the capacitors of the capacitor module 500, respectively. AC power is generated at the connection between the upper arm circuit and the lower arm circuit, respectively, and the connection between the upper arm circuit and the lower arm circuit of each upper and lower arm series circuit is connected to the AC side terminal 320B of each power module 300. ing. The AC side terminal 320B of each power module 300 of each phase is connected to the AC output terminal of the power converter 200, and the generated AC power is supplied to the stator winding of the motor generator 192 or 194.

The control circuit 172 controls the switching timing of the active element 155 for the upper arm and the active element 157 of the lower arm based on the input information from the control device or the sensor (for example, the current sensor 180) on the vehicle side. Generate a timing signal. The driver circuit 174 generates a drive signal for switching the active element 155 for the upper arm and the active element 157 for the lower arm based on the timing signal output from the control circuit 172.
In addition, 181 and 182, 188 are connectors.

The upper / lower arm series circuit includes a temperature sensor (not shown), and the temperature information of the upper / lower arm series circuit is input to the microcomputer. Further, voltage information on the DC positive electrode side of the upper / lower arm series circuit is input to the microcomputer. The microcomputer performs overtemperature detection and overvoltage detection based on the information, and when overtemperature or overvoltage is detected, the switching operation of all the active elements 155 for the upper arm and the active element 157 for the lower arm is performed. Stop and protect the upper / lower arm series circuit from overtemperature or overvoltage.

FIG. 17 is an external perspective view showing an example of the power conversion device shown in FIG. 16, and FIG. 18 is a sectional view taken along line XVIII-XVIII of the power conversion device shown in FIG.
The power conversion device 200 is composed of a lower case 11 and an upper case 10, and includes a housing 12 formed in a substantially rectangular parallelepiped shape. An electric circuit device 400, a capacitor module 500 (see FIG. 18), and the like are housed inside the housing 12. The electric circuit device 400 has a cooling flow path, and a cooling water inflow pipe 13 and a cooling water outflow pipe 14 communicating with the cooling flow path project from one side surface of the housing 12.

As shown in FIG. 17, the lower case 11 has an opening on the upper side, and the upper case 10 is attached to the lower case 11 by closing the opening of the lower case 11. The upper case 10 and the lower case 11 are formed of an aluminum alloy or the like, and are sealed and fixed to the outside. The upper case 10 and the lower case 11 may be integrated. Since the housing 12 has a simple rectangular parallelepiped shape, it can be easily attached to a vehicle or the like and can be easily produced.

A connector 17 is attached to one side surface of the housing 12, and an AC terminal 18 is connected to the connector 17. Further, a connector 21 is provided on the surface from which the cooling water inflow pipe 13 and the cooling water outflow pipe 14 are led out.

As shown in FIG. 18, the electric circuit device 400 is housed in the housing 12.
A control circuit 172 and a driver circuit 174 are arranged above the electric circuit device 400, and a capacitor module 500 is housed below the electric circuit device 400. The AC side terminal 320B of the power module 300 penetrates the current sensor 180 and is joined to the bus bar 361. Further, the positive electrode side terminal 315B and the negative electrode side terminal 319B, which are the DC terminals of the power module 300, are joined to the positive and negative electrode terminals 362A and 362B of the capacitor module 500, respectively.
In the power module 300 shown in FIG. 18, the AC side terminal 320B is not bent and extends straight. Further, the positive electrode side terminal 315B and the negative electrode side terminal 319B have a short shape cut on the root side.

In the above embodiment, it is preferable that the interposition portion 350 is formed of a member having a structure in which deformation is irreversible. However, by forming the upper and lower covers 340a and 340b with members having a slightly higher rigidity, the interposition portion 350 can be formed with a member other than the member having an irreversible deformation.

In the above embodiment, the electric circuit device 400 is exemplified as a 6in1 package having six upper / lower arm circuits 305a and 305b. However, the electric circuit device 400 can be a package having one or more upper / lower arm circuits 305a and 305b.

In the above embodiment, the flow path forming body 340 is exemplified as a structure including the upper and lower covers 340a and 340b. However, the present invention can also be applied to the flow path forming body 340 having only one of the upper and lower covers 340a and 340b.

In the above embodiment, the structure is exemplified in which the emitter-side and collector-side wiring boards 422 and 423 are provided between the first to fourth conductors 410 to 413 and the heat dissipation base 332. However, the first to fourth conductors 410 to 413 and the heat dissipation base 332 may be directly thermally coupled to each other.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. The various embodiments and modifications described above may be combined or modified as appropriate, and other aspects considered within the scope of the technical idea of the present invention are also included within the scope of the present invention.

150 Semiconductor element 172 Control circuit 200 Power converter 300 Power module 310 Electric circuit body 330 Heat dissipation part 331, 31A to 331D Fin 331S Side 331T Upper end surface 332 Heat dissipation base 340 Flow path forming body 340a Top cover 340b Bottom cover 350, 350A to 350C interposed portion 351 recess 351S side 360 a sealing resin 400 electric circuit device 410 to 413 first to fourth conductor C _c gap f _c bypass flow

Claims (10)

An electric circuit body having semiconductor elements and conductors,
A heat radiating portion having a heat radiating base and a plurality of fins, and the heat radiating base being thermally coupled to the conductor,
A cover provided on the opposite side of the electric circuit body of the heat radiating portion so as to cover the heat radiating portion.
It is provided with an interposition portion provided in contact with the facing surface of the cover facing the heat radiating portion and forming a flow path between the cover and the heat radiating base.
The fins have an upper end surface and a side surface, respectively.
The interposition portion is an electric circuit device having recesses on the upper end surface of each of the fins and a portion of the side surface in the vicinity of the upper end surface. In the electric circuit apparatus according to claim 1,
An electric circuit device in which a side surface of the recess of the interposition portion is in contact with a part of the side surface of the fin near the upper end surface. In the electric circuit apparatus according to claim 1,
The interposition portion is an electric circuit device having a configuration in which deformation is irreversible. In the electric circuit apparatus according to claim 1,
The interposition portion is an electric circuit device formed of any of a non-woven fabric, a paste material, and a cured resin material. In the electric circuit apparatus according to claim 1,
The interposition portion is an electric circuit device fixed to a facing surface facing the heat radiating portion of the cover. In the electric circuit apparatus according to claim 1,
An electric circuit device in which at least the bottom surface of a recess of a part of the interposition portion is separated from the upper end surface of each fin in a state where the cover is deformed by the hydraulic pressure of the coolant flowing in the flow path. The electric circuit device according to any one of claims 1 to 6.
A power conversion device including a control unit that controls the semiconductor element of the electric circuit body to perform power conversion. Preparing an electric circuit body having semiconductor elements and conductors,
The heat dissipation base and the heat dissipation base of the heat dissipation part having a plurality of fins are thermally coupled to the conductor.
A cover covering the heat radiating portion is provided on the opposite side of the electric circuit body of the heat radiating portion.
The cover includes providing an interposition portion that comes into contact with the facing surface facing the heat radiating portion and forms a flow path between the cover and the heat radiating base.
The fins have an upper end surface and a side surface, respectively.
The provision of the interposition portion is a method for manufacturing an electric circuit device, which comprises forming a recess in which a part of the upper end surface and the side surface of each of the fins near the upper end surface is inserted. In the method for manufacturing an electric circuit device according to claim 8.
Providing the recess in the interposition portion is a method for manufacturing an electric circuit device, which comprises providing the side surface of the recess so as to be in contact with a part of the side surface of the fin near the upper end surface. In the method for manufacturing an electric circuit device according to claim 8.
Forming the recess in the interposition portion is a method for manufacturing an electric circuit device using the interposition portion having a structure in which deformation is irreversible.