JP2022098583A - Electric circuit body and power conversion device - Google Patents

Abstract

To prevent deterioration in heat dissipation due to the impossibility of forming a fin in a slit part of a fin base.SOLUTION: An electric circuit body includes: a power semiconductor element; a conductor plate to be joined to the power semiconductor element; a cooling member arranged to face the power semiconductor element with the conductor plate sandwiched therebetween; a sheet member sandwiched between the conductor plate and the cooling member and bonded or joined to the conductor plate; and a sealing member which seals the power semiconductor element, the conductor plate, the sheet member and the cooling member. The cooling member includes: a fin base of a predetermined thickness having one surface exposed from the sealing member; a plurality of fins erected on the one surface of the fin base; and an end part covered with the sealing member at the outer periphery of the fin base. In the conductor plate region of the fin base facing the conductor plate and the outer periphery region on the outer periphery of the conductor plate region, each interval between the fins arranged in the outer periphery region is equal to or less than twice the thickness of the fin base.SELECTED DRAWING: Figure 7

Description

The present invention relates to an electric circuit body and a power conversion device.

Since the power conversion device by switching the power semiconductor element has high conversion efficiency, it is widely used for consumer use, in-vehicle use, railway use, substation equipment, and the like. Since the power semiconductor element generates heat when energized, a cooling member is provided in the device incorporating the power semiconductor element. The cooling member includes a fin base and a plurality of fins erected on the fin base, and cools the power semiconductor element by circulating a refrigerant between the fins.

In Patent Document 1, in a semiconductor device in which a sealing member is sealed in a transfer molding process, a slit penetrating in the thickness direction of the fin is formed, and in the molding die, a strut portion is provided at a position corresponding to the slit. Disclosed is a technique for suppressing deformation of the fin base at the strut portion with respect to the pressure at the time of molding.

International Publication WO2013 / 114647

The device described in Patent Document 1 has a problem that heat dissipation is lowered because fins cannot be formed in the slit portion of the fin base.

The electric circuit body according to the present invention includes a power semiconductor element, a conductor plate bonded to the power semiconductor element, a cooling member arranged so as to face the power semiconductor element with the conductor plate interposed therebetween, and the conductor plate. A sheet member sandwiched between the cooling member and adhered to or bonded to the conductor plate, and a sealing member for sealing the power semiconductor element, the conductor plate, the sheet member, and the cooling member. The cooling member includes a fin base having a predetermined thickness whose one surface is exposed from the sealing member, a plurality of fins erected on the one surface of the fin base, and the above-mentioned electric circuit body. The outer periphery of the fin base is provided with an end portion covered with the sealing member, and is arranged in the outer peripheral region in a conductor plate region facing the conductor plate of the fin base and an outer peripheral region of the outer periphery of the conductor plate region. The distance between the fins is not more than twice the thickness of the fin base.

According to the present invention, it is possible to prevent the fin base from being occupied by slits other than the fins, and to suppress deformation of the fin base without deteriorating heat dissipation.

It is a top view of an electric circuit body. It is sectional drawing of XX line of an electric circuit body. It is sectional drawing of the YY line of an electric circuit body. It is sectional drawing of the power module. It is sectional drawing which shows the manufacturing method of (a)-(c) electric circuit body. (D)-(f) It is sectional drawing which shows the manufacturing method of the electric circuit body. (A) (b) is an enlarged view in the transfer molding process. (A) (b) It is a figure explaining the relationship between fin spacing and fin base thickness. It is a top view of the fin base in which fins having a rectangular cross-sectional shape are erected. It is a top view of the fin base in which fins having a circular cross-sectional shape are erected. It is a top view of the fin base in which fins having a circular cross-sectional shape are erected on the boundary. It is a partially enlarged view of the plan view of the fin base in which fins are erected. It is a semi-transmissive plan view of a power module. It is a circuit diagram of a power module. It is a circuit diagram of a power conversion device using an electric circuit body. It is an external perspective view of a power conversion device. It is sectional drawing of the power conversion apparatus.

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 the sake of 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 positions, sizes, shapes, ranges, etc. of each component shown in the drawings may not represent the actual positions, sizes, shapes, ranges, 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 the electric circuit body 400, and FIG. 2 is a cross-sectional view taken along the line XX shown in FIG. 1 of the electric circuit body 400. FIG. 3 is a cross-sectional view taken along the line YY shown in FIG. 1 of the electric circuit body 400.
As shown in FIG. 1, the electric circuit body 400 includes three power modules 300 and a cooling member 340. The power module 300 has a function of converting a direct current and an alternating current by using a power semiconductor element, and generates heat when energized. Therefore, the structure is such that the refrigerant flows through the cooling member 340 to cool the cooling member. As the refrigerant, water or an antifreeze solution in which ethylene glycol is mixed with water is used. In the cooling member 340, a plurality of pin-shaped fins are erected on the fin base of the cooling member 340. The cooling member 340 is preferably made of aluminum, which has high thermal conductivity and is lightweight. The cooling member 340 is manufactured by extrusion molding, forging, brazing, or the like.

The power module 300 includes a positive electrode side terminal 315B and a negative electrode side terminal 319B connected to a capacitor module 500 (see FIG. 15 described later) of a DC circuit on one side. On the other side of the positive electrode side terminal 315B and the negative electrode side terminal 319B, a power terminal through which a large current flows, such as an AC side terminal 320B connected to the motor generators 192 and 194 of the AC circuit (see FIG. 15 described later), is provided. Further, the other side is provided with a signal terminal used for controlling a power module 300 such as a lower arm gate signal terminal 325L, a mirror emitter signal terminal 325M, a Kelvin emitter signal terminal 325K, and an upper arm gate signal terminal 325U.

As shown in FIG. 2, an active element 155 and a diode 156 are provided as the first power semiconductor element forming the upper arm circuit. As the semiconductor material constituting the active element 155, for example, Si, SiC, GaN, GaO, C or the like can be used. When the body diode of the active element 155 is used, the diode 156 may be omitted. The collector side of the active element 155 and the cathode side of the diode 156 are joined to the second conductor plate 431. A first conductor plate 430 is bonded to the emitter side of the active element 155 and the anode side of the diode 156. Solder may be used for these joinings, or sintered metal may be used. The first conductor plate 430 and the second conductor plate 431 are not particularly limited as long as they are materials having high electrical conductivity and thermal conductivity, but copper-based or aluminum-based materials are preferable. These may be used alone, or may be plated with Ni, Ag, or the like in order to improve the bondability with solder or sintered metal.

A cooling member 340 is brought into close contact with the first conductor plate 430 via the first sheet member 440. The first sheet member 440 is configured by laminating a resin insulating layer and a metal foil. A heat conductive member (not shown) is provided between the first sheet member 440 and the cooling member 340, and the metal leaf side of the first sheet member 440 is brought into close contact with the heat conductive member. The heat conductive member is not particularly limited as long as it is a material having high thermal conductivity, but it is preferable to use a high heat conductive material such as a metal, ceramics, or carbon-based material in combination with a resin material.

The cooling member 340 is brought into close contact with the second conductor plate 431 via the second sheet member 441. The second sheet member 441 is configured by laminating a resin insulating layer and a metal foil. A heat conductive member is provided between the second sheet member 441 and the cooling member 340, and the metal leaf side of the second sheet member 441 is brought into close contact with the heat conductive member. From the viewpoint of heat dissipation, it is desirable that the width of the cooling member 340 is wider than the width of the seat members 440 and 441.

The sheet members 440 and 441 are sandwiched between the conductor plates 430 and 431 and the cooling member 340 and adhered or joined to the conductor plates 430 and 431. The power semiconductor element 155, 156, the conductor plate 430, 431, the sheet member 440, 441, and the cooling member 340 are integrally sealed by the sealing member 360 by the transfer molding process to form the electric circuit body 400.

The cooling member 340 is arranged so as to face the power semiconductor elements 155 and 156 with the conductor plates 430 and 431 interposed therebetween. The cooling member 340 includes a fin base 371 having a predetermined thickness whose one surface is exposed from the sealing member 360, and a plurality of fins 370 erected on one surface of the fin base 371. The end of the fin base 371 is covered with a sealing member 360 on the outer circumference of the fin base 371. Although the details will be described later, in the conductor plate region S1 (see FIG. 7A) facing the conductor plates 430 and 431 of the cooling member 340 and the outer peripheral region S2 (see FIG. 7A) of the outer periphery of the conductor plate region S1. The distance between the fins 370 arranged in the outer peripheral region S2 is not more than twice the thickness of the fin base 371.

As shown in FIG. 3, the first conductor plate 430, the second conductor plate 431, the third conductor plate 432, and the fourth conductor plate 433 have a role of energizing a current, as well as a first power semiconductor element 155, 156. It plays a role as a heat transfer member that transfers heat generated by the second power semiconductor element 157 and 158 to the cooling member 340. Since the potentials of the conductor plates 430, 431, 432, 433 and the cooling member 340 are different, as shown in FIG. 2, the sheet member 440, between the conductor plates 430, 431, 432, 433 and the cooling member 340, Via 441. The first power semiconductor element 155, 156 and the second power semiconductor element 157, 158 may be simply referred to as a power semiconductor element 159.

The sheet members 440 and 441 are not particularly limited as long as they have adhesiveness to the cooling member 340 and the conductor plates 430, 431, 432, and 433, but an epoxy resin-based resin insulating layer in which a powdered inorganic filler is dispersed may be used. desirable. This is because the adhesiveness and the heat dissipation are well-balanced.

The conductor plates 430, 431, 432, and 433 are preferably made of a material having high electric conductivity and high thermal conductivity, and are preferably a metal-based material such as copper or aluminum, or a metal-based material and high thermal conductivity diamond, carbon, ceramic, or the like. It is also possible to use the composite material of.

FIG. 4 is a cross-sectional perspective view of the power module 300 in the XX line shown in FIG. As shown in FIG. 4, the end of the first sheet member 440 and the end of the fin base 371 are covered by the sealing member 360. The first sheet member 440 that overlaps the surface of the first conductor plate 430 is a heat dissipation surface. The cooling member 340 is brought into close contact with the heat radiating surface of the first sheet member 440 to ensure the close contact with the cooling member 340 so that the heat radiating property is not impaired.

The cooling member 340 is preferably made of aluminum, which has high thermal conductivity and is lightweight. Manufactured by extrusion, forging, brazing, etc. The cooling member 340 forms an adhesive and watertight structure via a sealing member (not shown) on the fin base 371. The outer peripheral portion of the fin base 371 has a thin-walled portion 374 that prevents resin leakage from the transfer mold, and this portion is deformed during transfer mold molding to absorb thickness variations and prevent resin leakage from the transfer mold. is doing.

5 (a) to 5 (c) and FIGS. 6 (d) to 6 (f) are sectional views showing a method of manufacturing the electric circuit body 400. 5 (a) to 5 (c) and 6 (d) are cross-sectional views of one power module on the YY line shown in FIG. 1, and FIGS. 6 (e) to 6 (f) are X shown in FIG. -The cross-sectional view for one power module in X-ray is shown.

FIG. 5A is a diagram showing a solder connection process and a wire bonding process. The collector side of the active element 155, which is the first power semiconductor element, is connected to the second conductor plate 431. The emitter side of the active element 155 is connected to the first conductor plate 430. Similarly, the collector side of the active element 157, which is the second power semiconductor element, is connected to the fourth conductor plate 433. The emitter side of the active element 157 is connected to the third conductor plate 432. In this way, the circuit body 310 is formed. Then, a fin base 371 having a first sheet member 440 and fins 370 on one surface of the circuit body 310 is provided, and a fin base 371 having a second sheet member 441 and fins 370 on the other surface of the circuit body 310. Is arranged to provide the assembly 311.

5 (b) to 5 (c) are views showing the transfer molding process.
As shown in FIG. 5B, the transfer molding device 601 includes a spring mechanism 602. The vacuum degassing mechanism for vacuum-adsorbing the sheet members 440, 441 and the like to the mold is not shown. The assembly 311 preheated to 175 ° C. is installed in the mold in the mold preheated to a constant temperature of 175 ° C.

Next, as shown in FIG. 5 (c), the mold is closed and the sealing member 360 is injected into the mold cavity. At this time, the thin portion 374 provided on the outer periphery of the fin base 371 is deformed by the mold to absorb the variation in the thickness of the assembly 311 and prevent the sealing member 360 from flowing into the fin 370 side. It becomes a lid. Further, when the mold is closed, the tip of the fin 370 is pressed by the spring mechanism 602, and this pressure is larger than the injection pressure of the sealing member 360 at the time of transfer mold molding. When the pressure applied by the spring mechanism 602 is applied to the heating in the mold, the curing reaction of the sheet members 440 and 441 proceeds, and the sheet members 440 and 441 are attached to the fin base 371 and the conductor plates 430, 431, 432 and 433. Glue. However, the fin base 371 may be deformed by the injection pressure of the sealing member 360 at the time of transfer mold molding. In this embodiment, as will be described later, the deformation of the fin base 371 is suppressed.

FIG. 6D is a diagram showing a curing process. The power module 300 sealed by the sealing member 360 is taken out from the transfer mold device 601 and cooled at room temperature to be cured for 2 hours or more.

FIG. 6E is a diagram showing an installation process of the cooling member 340. A seal member 372 is arranged around the fin base 371, and the lid 373 is adhered to the fin base 371 to form a cooling member 340.

FIG. 6 (f) is a diagram showing an electric circuit body 400 manufactured by the above steps. In this way, the cooling members 340 are installed on both sides of the power module 300 to manufacture the electric circuit body 400.

FIG. 7 is an enlarged view of the dotted line portion H in FIG. 5 (c) in the transfer molding process. FIG. 7A shows the present embodiment, and FIG. 7B shows a comparative example to which the present embodiment is not applied.

FIG. 7A shows a transfer molding process in which the mold is closed and the pressing force P by the spring mechanism 602 is applied. Then, the pressing force P is also applied to the tip of the fin 370 by the spring mechanism 602. Further, in the state where the sealing member 360 is injected, the injection pressure Q is applied to the fin base 371 and the conductor plate 432 as hydrostatic pressure. Since the pressing force P by the spring mechanism 602 is set to be larger than the injection pressure Q, the seat member 440 is heated, pressurized and adhered between the fin base 371 and the conductor plate 432. In the present embodiment, as will be described in detail later, in the outer peripheral region S2 of the outer peripheral region S1 of the conductor plate region S1 facing the conductor plate 432 of the fin base 371 and the conductor plate region S1, the fins 370 arranged in the outer peripheral region S2 are connected to each other. The spacing should be no more than twice the thickness of the fin base 371. This suppresses the deformation of the fin base 371.

In the comparative example shown in FIG. 7B, when the distance between the fins 370 is large and the thickness of the fin base 371 is thin, the injection pressure Q causes deformation R of the fin base 371 between the fins 370 and the fins 370. In this case, since the fin base 371 is separated from the sheet member 440 at the end of the conductor plate 432, the adhesion of the sheet member 440 becomes poor. The sealing member 360 penetrates into the portion where the deformation R of the fin base 371 occurs, but the sealing member 360 does not penetrate into the gap of 20 μm or less in order to suppress the resin burr to the mold. As a result, the amount of deformation of the fin base 371 may cause peeling of the sheet member 440 at the end of the conductor plate 432 with an air layer, and in this case, the insulation and heat dissipation of the electric circuit body 400 are deteriorated.

8 (a) and 8 (b) are diagrams illustrating the relationship between the distance between the fins 370 and the thickness of the fin base 371. The distance (distance) between the fins 370 and the fins 370 is D, and the thickness of the fin base 371 between the fins 370 and the fins 370 is T.
FIG. 8A shows the case of D ≦ 2T. The pressing force P by the spring mechanism 602 is first applied to the tip of the fin 370. This pressing force P spreads at an angle of about 45 degrees as shown by the dotted line t showing the thickness T of the fin base 371. When the relationship of D≤2T is satisfied, the entire back surface of the fin base 371 becomes a region P1 in which the surface pressure is high due to the applied pressure P of the spring mechanism 602.

FIG. 8B shows the case where D> 2T. On the back surface of the fin base 371, the thickness T of the fin base 371 is spread at an angle of about 45 degrees as shown by the dotted line t by the pressing force P by the spring mechanism 602. As a result, when the thickness T of the fin base 371 is thin or the interval D is large, a region P1 having a high surface pressure and a region P2 having a low surface pressure are formed. In the region P2 where the surface pressure is low, the fin base 371 is deformed because the injection pressure Q in the transfer molding process cannot be countered. From such a principle, it has been clarified that when the tip of the fin 370 is supported by a mold in the transfer molding process, it is necessary to satisfy the relationship of D≤2T in order to suppress the deformation of the fin base 371. .. It should be noted that this relationship does not have to be satisfied in all the regions where the fins 370 are provided.

FIG. 9 is a plan view of the fin base 371 in which the fin 370 is erected. In this figure, the case where the cross-sectional shape of the fin 370 is rectangular will be described as an example.
In the conductor plate region S1 facing the conductor plate of the fin base 371, the distance (interval) D of the fins 370 and the thickness T of the fin base 371 do not have to satisfy the relationship of D≤2T, and the power semiconductor element 159 The fins 370 required for heat dissipation may be appropriately arranged. On the other hand, the injection pressure Q in the transfer molding process is applied to the fin base 371 via the sealing member 360 in the outer peripheral region S2 on the outer periphery of the conductor plate region S1. Therefore, the distance d1 between the fins 370 arranged in the outer peripheral region S2 is set to be twice or less the thickness of the fin base 371 so as to satisfy the relationship of D ≦ 2T. As a result, by suppressing the deformation of the fin base 371, the sheet member 440 is prevented from peeling off, and the insulation and heat dissipation of the electric circuit body 400 are kept good.

Further, the distance d2 between the fins 370 arranged in the conductor plate region S1 and the fins 370 arranged in the outer peripheral region S2 adjacent to the fins 370 is not more than twice the thickness T of the fin base 371. Here, the fins 370 arranged in the conductor plate region S1 may be arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2. When the fin 370 is on the boundary between the conductor plate region S1 and the outer peripheral region S2, the deformation of the fin base 371 can be further suppressed.

Further, the distance d3 between the fins 370 arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2 is not more than twice the thickness of the fin base 371. Here, the distance d3 between the fins arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2 may be narrower than the distance d4 between the fins arranged in the conductor plate region S1.
Further, the distance d5 between the fins 370 arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2 and the fins 370 arranged in the outer peripheral region S2 is not more than twice the thickness of the fin base 371.

The distance d1 of the fins 370 arranged parallel to the flow F of the refrigerant flowing through the cooling member is narrower than the distance d3 of the fins 370 arranged perpendicular to the flow F of the refrigerant.

FIG. 10 is a plan view of the fin base 371 in which the fins 370 are erected. In this figure, the case where the cross-sectional shape of the fin 370 is circular will be described as an example.
In the conductor plate region S1 facing the conductor plate of the fin base 371, the distance (interval) D of the fins 370 and the thickness T of the fin base 371 do not have to satisfy the relationship of D≤2T, and the power semiconductor element 159 The fins 370 required for heat dissipation may be appropriately arranged. On the other hand, the injection pressure Q in the transfer molding process is applied to the fin base 371 via the sealing member 360 in the outer peripheral region S2 on the outer periphery of the conductor plate region S1. Therefore, the distance d1 between the fins 370 arranged in the outer peripheral region S2 is set to be twice or less the thickness of the fin base 371 so as to satisfy the relationship of D ≦ 2T. As a result, by suppressing the deformation of the fin base 371, the sheet member 440 is prevented from peeling off, and the insulation and heat dissipation of the electric circuit body 400 are kept good.

Further, the distance d2 between the fins 370 arranged in the conductor plate region S1 and the fins 370 arranged in the outer peripheral region S2 adjacent to the fins 370 is not more than twice the thickness T of the fin base 371. Here, the fins 370 arranged in the conductor plate region S1 may be arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2. When the fin 370 is on the boundary between the conductor plate region S1 and the outer peripheral region S2, the deformation of the fin base 371 can be further suppressed.

The distance d1 of the fins 370 arranged parallel to the flow F of the refrigerant flowing through the cooling member is narrower than the distance d3 of the fins 370 arranged perpendicular to the flow F of the refrigerant.

FIG. 11 is a plan view of the fin base 371 in which the fins 370 are erected. In this figure, a case where the cross-sectional shape of the fin 370 is circular and the fin 370 is arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2 will be described as an example.
The distances d1 and d3 between the fins 370 arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2 are set to be twice or less the thickness of the fin base 371. As a result, by suppressing the deformation of the fin base 371, the sheet member 440 is prevented from peeling off, and the insulation and heat dissipation of the electric circuit body 400 are kept good.

Here, even if the distances d1 and d3 between the fins 370 arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2 are arranged narrower than the distance d4 between the fins arranged in the conductor plate region S1. good.
Further, the distance d5 between the fins 370 arranged on the boundary between the conductor plate region S1 and the outer peripheral region S2 and the fins 370 arranged in the outer peripheral region S2 is not more than twice the thickness of the fin base 371.

The distance d1 of the fins 370 arranged parallel to the flow F of the refrigerant flowing through the cooling member is narrower than the distance d3 of the fins 370 arranged perpendicular to the flow F of the refrigerant.

FIG. 12 is a partially enlarged view of the plan view of the fin base 371 in which the fins 370 are erected.
Let Dv be the distance between fins in the direction parallel to the flow F of the refrigerant, and Dp be the distance between fins in the direction perpendicular to the flow F of the refrigerant. When Dp is small, it is difficult for the refrigerant to flow and the pressure loss in the water channel becomes high, and it becomes necessary to increase the output of the pump to allow the refrigerant to flow. On the other hand, even if Dv is reduced, the pressure loss of the water channel does not increase. Therefore, by setting Dp> Dv, a decrease in pressure loss in the water channel is suppressed. On top of that, the intervals Dp and d1 of the fins 370 in the outer peripheral region S2 can be reduced to satisfy D ≦ 2T.

According to this embodiment, the deformation of the fin base 371 due to the transfer mold molding can be suppressed, the sheet member 440 can be prevented from peeling off at the end of the conductor plate 432, and the insulation and heat dissipation of the electric circuit body 400 are good. Can be kept in.

FIG. 13 is a semi-transmissive plan view of the power module 300 in this embodiment. FIG. 14 is a circuit diagram of the power module 300 in this embodiment.

As shown in FIGS. 13 and 14, the positive electrode side terminal 315B outputs from the collector side of the upper arm circuit and is connected to the positive electrode side of the battery or the capacitor. The upper arm gate signal terminal 325U outputs from the gate and emitter sense of the active element 155 of the upper arm circuit. The negative electrode side terminal 319B outputs from the emitter side of the lower arm circuit and is connected to the negative electrode side of the battery or the capacitor or GND. The lower arm gate signal terminal 325L outputs from the gate and emitter sense of the active element 157 of the lower arm circuit. The AC side terminal 320B outputs from the collector side of the lower arm circuit and is connected to the motor. When grounding to the neutral point, the lower arm circuit is connected to the negative electrode side of the capacitor instead of GND.

Further, the first conductor plate (upper arm circuit emitter side) 430 and the second conductor plate (upper arm circuit collector side) 431 are arranged above and below the active element 155 and the diode 156 of the first power semiconductor element (upper arm circuit). To. A third conductor plate (lower arm circuit emitter side) 432 and a fourth conductor plate (lower arm circuit collector side) 433 are arranged above and below the active element 157 and the diode 158 of the second power semiconductor element (lower arm circuit).

The power module 300 of the present embodiment has a 2in1 structure in which two arm circuits, an upper arm circuit and a lower arm circuit, are integrated into one module. In addition to this, a structure in which a plurality of upper arm circuits and lower arm circuits are integrated into one module may be used. In this case, the number of output terminals from the power module 300 can be reduced to reduce the size.

FIG. 15 is a circuit diagram of a power conversion device 200 using the electric circuit body 400.
The power conversion device 200 includes inverter circuits 140 and 142, an inverter circuit 43 for auxiliary equipment, and a capacitor module 500. The inverter circuits 140 and 142 are composed of an electric circuit body 400 (not shown) including a plurality of power modules 300, and a three-phase bridge circuit is formed by connecting them. 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 140 and the inverter circuit 142 have the same basic circuit configuration, and the control method and operation are also basically the same. Since the outline of the circuit-like operation of the inverter circuit 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 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. 13, the cathode electrode of the diode 156 and 158 is electrically connected to the collector electrode of the active element 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, and 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 362A and 362B 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 / 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 is for controlling 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 control circuit 172. Further, voltage information on the DC positive electrode side of the upper / lower arm series circuit is input to the control circuit 172. The control circuit 172 performs overtemperature detection and overvoltage detection based on the information, and when overtemperature or overvoltage is detected, switching of all the active elements 155 for the upper arm and the active element 157 for the lower arm. Stop the operation and protect the upper / lower arm series circuit from overtemperature or overvoltage.

16 is an external perspective view of the power conversion device 200 shown in FIG. 15, and FIG. 17 is a cross-sectional perspective view of the power conversion device 200 shown in FIG. 16 taken along the line XV-XV.
As shown in FIG. 16, 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 body 400, a capacitor module 500, and the like are housed inside the housing 12. The electric circuit body 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. The lower case 11 is opened on the upper side (Z direction), 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 and configured. Since the housing 12 has a simple rectangular parallelepiped shape, it can be easily attached to a vehicle or the like, and productivity is also improved.

A connector 17 is attached to one side surface of the housing 12 in the longitudinal direction, 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. 17, the electric circuit body 400 is housed in the housing 12. A control circuit 172 and a driver circuit 174 are arranged above the electric circuit body 400, and a capacitor module 500 is housed on the DC terminal side of the electric circuit body 400. By arranging the capacitor module at the same height as the electric circuit body 400, the power conversion device 200 can be made thinner and the degree of freedom of installation in a vehicle is improved. The AC side terminal 320B of the electric circuit body 400 penetrates the current sensor 180 and is joined to the bus bar. Further, the positive electrode side terminal 315B and the negative electrode side terminal 319B, which are the DC terminals of the electric circuit body 400, are joined to the positive and negative electrode terminals (DC terminals 362A and 362B in FIG. 13) of the capacitor module 500, respectively.

According to the embodiment described above, the following effects can be obtained.
(1) The electric circuit body 400 sandwiches a power semiconductor element 159, a conductor plate 430, 431, 432, 433 joined to the power semiconductor element 159, and a conductor plate 430, 431, 432, 433, and the power semiconductor element 159. The sheet member 440 is sandwiched between the conductor plate 430, 431, 432, 433 and the cooling member 340, and is bonded or bonded to the conductor plate 430, 431, 432, 433. 441, and an electric circuit body 400 including a power semiconductor element 159, a conductor plate 430, 431, 432, 433, a sheet member 440, 441, and a sealing member 360 for sealing the cooling member 340. The cooling member 340 includes a fin base 371 having a predetermined thickness whose one surface is exposed from the sealing member 360, a plurality of fins 370 standing on one surface of the fin base 371, and a sealing member on the outer periphery of the fin base 371. The end portion covered with 360 is provided, and is arranged in the outer peripheral region S2 in the outer peripheral region S2 of the outer peripheral region S1 of the conductor plate region S1 facing the conductor plates 430, 431, 432, and 433 of the fin base 371 and the conductor plate region S1. The distance between the fins 370 is less than twice the thickness of the fin base 371. As a result, it is possible to prevent the fin base from being occupied by slits other than the fins, and to suppress deformation of the fin base without deteriorating heat dissipation.

The present invention is not limited to the above-described embodiment, and other embodiments considered within the scope of the technical idea of the present invention are also included within the scope of the present invention as long as the features of the present invention are not impaired. .. Further, the configuration may be a combination of the above-described embodiment and a plurality of examples.

155 ... 1st power semiconductor element (upper arm circuit active element), 156 ... 1st power semiconductor element (upper arm circuit diode), 157 ... 2nd power semiconductor element (lower arm circuit active element), 158 ... Second power semiconductor element (lower arm circuit diode), 159 ... Power semiconductor element, 172 ... Control circuit, 174 ... Driver circuit, 180 ... Current sensor, 181, 182, 188 ... Connector, 192, 194 ... Motor generator, 200 ... Power converter, 300 ... Power module, 310 ... Circuit body, 311 ... Assembly, 315B ... Positive terminal , 319B ... Negative side terminal, 320B ... AC side terminal, 325 ... Signal terminal, 325K ... Kelvin emitter signal terminal, 325L ... Lower arm gate signal terminal, 325M ... Mirror emitter signal Terminal, 325U ... Upper arm gate signal terminal, 340 ... Cooling member, 360 ... Sealing member, 370 ... Fin, 371 ... Fin base, 372 ... Seal member, 400 ... -Electric circuit body, 430 ... 1st conductor plate (upper arm circuit emitter side), 431 ... 2nd conductor plate (upper arm circuit collector side), 432 ... 3rd conductor plate (lower arm circuit emitter side) Side), 433 ... 4th conductor plate (lower arm circuit collector side), 440 ... 1st sheet member (emitter side), 441 ... 2nd sheet member (collector side), 500 ... condenser Module, 601 ... Transfer mold device, 602 ... Spring mechanism, D ... Fin spacing, P ... Pressurization by spring mechanism, Q ... Sealing member injection pressure, S1 ... Conductor plate region, S2 ... outer peripheral region, T ... fin base thickness.

Claims (8)

It is sandwiched between a power semiconductor element, a conductor plate joined to the power semiconductor element, a cooling member arranged so as to face the power semiconductor element with the conductor plate interposed therebetween, and the conductor plate and the cooling member. An electric circuit body comprising a sheet member that is bonded or bonded to the conductor plate, and a sealing member that seals the power semiconductor element, the conductor plate, the sheet member, and the cooling member. ,
The cooling member includes a fin base having a predetermined thickness whose one surface is exposed from the sealing member, a plurality of fins erected on the one surface of the fin base, and the sealing member on the outer periphery of the fin base. In the outer peripheral region of the outer peripheral region of the conductor plate region facing the conductor plate of the fin base and the outer peripheral region of the conductor plate region, the distance between the fins arranged in the outer peripheral region is the fin. An electric circuit body that is less than twice the thickness of the base. In the electric circuit body according to claim 1,
The distance between the first fin arranged in the conductor plate region and the second fin arranged in the outer peripheral region adjacent to the first fin is not more than twice the thickness of the fin base. .. In the electric circuit body according to claim 2,
The first fin is an electric circuit body arranged on a boundary between the conductor plate region and the outer peripheral region. In the electric circuit body according to claim 1,
An electric circuit body in which the distance between the first fins arranged on the boundary between the conductor plate region and the outer peripheral region is not more than twice the thickness of the fin base. In the electric circuit body according to claim 4,
An electric circuit body in which the distance between the first fins arranged on the boundary between the conductor plate region and the outer peripheral region is narrower than the distance between the fins arranged in the conductor plate region. In the electric circuit body according to claim 1,
An electric circuit body in which the distance between the fins arranged parallel to the flow of the refrigerant flowing through the cooling member is narrower than the distance between the fins arranged perpendicular to the flow of the refrigerant. In the electric circuit body according to any one of claims 1 to 6.
The conductor plates are arranged on both sides of the power semiconductor element, and one surface of each of the arranged conductor plates is joined to the power semiconductor element.
The sheet member is bonded or joined to the other surface of each conductor plate, respectively.
The cooling member is an electric circuit body bonded via each of the sheet members. A power conversion device comprising the electric circuit body according to any one of claims 1 to 6 and converting DC power into AC power.

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