Power module and power conversion device

Abstract

To provide a technique capable of improving the productivity of power modules.SOLUTION: A power module 202 includes: at least one power module unit 1 having an insulating substrate 10, semiconductor elements 21, 22 mounted on one surface of the insulating substrate, a fin base 70 including a base portion 72 bonded to the other surface of the insulating substrate 10 by solder 30 and a plurality of fins 71 protruding to the side opposed to the insulating substrate 10 in the base portion 72 and a case 51 covering the insulating substrate 10 and the semiconductor elements 21, 22; a water-cooling jacket 74 having at least one recess 76 for housing the fin base 70; and an adapter 73 disposed between the fin base 70 and the water-cooling jacket 74 to connect the fin base 70 and the water-cooling jacket 74. The outer peripheral portion of the adapter 73 protrudes to the outer peripheral side relative to the base portion 72 of the fin base 70.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a power module and a power conversion device. [Background technology]

[0002] As power modules are increasingly being installed in a wide range of products, from industrial equipment to home appliances and information terminals, high productivity is required for power modules.In particular, power modules installed in electric vehicles require high heat dissipation, so a structure in which an insulating substrate with semiconductor elements mounted thereon is bonded to a fin base and cooled in combination with a water-cooled jacket is becoming widespread.

[0003] For example, Patent Document 1 discloses a structure in which a fin base and a water-cooled jacket are screwed together with an O-ring interposed between them to achieve watertightness. In order to screw together the fin base and the water-cooled jacket, a flat mounting portion (corresponding to a base portion) is formed wider on the outer periphery side than the area in which the multiple fins are arranged in the fin base. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-248576 A Summary of the Invention [Problem to be solved by the invention]

[0005] The insulating substrate is often soldered to the fin base to reduce thermal resistance. The copper or aluminum fin base has a large heat capacity, and the entire fin base needs to be heated to the melting point of the solder or higher in order to be soldered.

[0006] In the technology described in Patent Document 1, the mounting portion of the fin base is formed to protrude significantly toward the outer periphery, and it takes a long time to heat and cool during soldering, which results in a problem of reduced productivity of the power module.

[0007] Therefore, an object of the present disclosure is to provide a technique capable of improving the productivity of power modules. [Means for solving the problem]

[0008] The power module according to the present disclosure comprises at least one power module part having an insulating substrate, a semiconductor element mounted on one side of the insulating substrate, a fin base including a base portion joined to the other side of the insulating substrate with solder and a plurality of fins protruding from the base portion to the side opposite the insulating substrate, and a case covering the insulating substrate and the semiconductor element, a water-cooled jacket having at least one recess for accommodating the fin base, and an adapter disposed between the fin base and the water-cooled jacket and connecting the fin base and the water-cooled jacket, and the outer periphery of the adapter protrudes outward more than the base portion of the fin base. Effect of the Invention

[0009] According to the present disclosure, the adapter is disposed between the fin base and the water-cooled jacket, and the fin base and the water-cooled jacket are connected via the adapter, so that it is not necessary to make the base portion of the fin base protrude significantly toward the outer periphery in order to attach the fin base to the water-cooled jacket. Since the amount of protrusion of the base portion can be reduced, it is possible to reduce the thermal energy required to bond the other surface of the insulating substrate to the base portion, and it is possible to shorten the time required for heating and cooling. This improves the productivity of the power module. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a top view of the power module according to the first embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of the power module according to the first embodiment. [Diagram 3] 2 is a cross-sectional view taken along line AA in FIG. 1. [Figure 4] FIG. 2 is a cross-sectional view taken along line BB in FIG. [Diagram 5] FIG. 4 is a cross-sectional view showing the internal structure of FIG. [Figure 6] 3A to 3C are cross-sectional views showing a method for manufacturing the power module according to the first embodiment. [Figure 7] 3A to 3C are cross-sectional views showing a method for manufacturing the power module according to the first embodiment. [Figure 8] 3A to 3C are cross-sectional views showing a method for manufacturing the power module according to the first embodiment. [Figure 9] FIG. 2 is a cross-sectional view of a power module according to a first modified example of the first embodiment. [Figure 10] FIG. 11 is a cross-sectional view of a power module according to a second modification of the first embodiment. [Figure 11] FIG. 11 is a top view of a power module according to a second embodiment. [Figure 12] FIG. 11 is a block diagram showing a configuration of a power conversion system to which a power conversion device according to a third embodiment is applied. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] <Embodiment 1> <Overall structure> The first embodiment will be described below with reference to the drawings. Fig. 1 is a top view of a power module 202 according to the first embodiment. Fig. 2 is an exploded perspective view of the power module 202 according to the first embodiment. Fig. 3 is a cross-sectional view taken along line AA in Fig. 1. Fig. 4 is a cross-sectional view taken along line BB in Fig. 1. Fig. 5 is a cross-sectional view showing the internal structure of Fig. 3, and is a drawing showing the internal structure of a case 51.

[0012] As shown in FIGS. 1 to 4, the power module 202 includes a power module section 1, a water-cooling jacket 74, and an adapter 73. The power module 202 includes a power module section 1, a water-cooling jacket 74, and an adapter 73.

[0013] First, a description will be given of the power module section 1. As shown in Fig. 5, the power module section 1 includes an insulating substrate 10, semiconductor elements 21 and 22, a main terminal 61, a signal terminal 62, a case 51, and a fin base 70.

[0014] The insulating substrate 10 is composed of a silicon nitride base material 10a, an upper conductor layer 10b made of copper formed on the upper surface of the base material 10a, and a lower conductor layer 10c made of copper formed on the lower surface of the base material 10a. The size of the base material 10a is 25 mm in width, 40 mm in depth, and 0.64 mm in thickness. The size of the upper conductor layer 10b and the lower conductor layer 10c is 23 mm in width, 38 mm in depth, and 0.8 mm in thickness.

[0015] The semiconductor elements 21 and 22 are mounted on the upper surface (one surface) of the insulating substrate 10 via solder 30. The solder 30 is composed of 96.5% tin, 3% silver, and 0.5% copper, and the melting point of the solder 30 is 217°C. The semiconductor element 21 is a silicon diode, and the size of the semiconductor element 21 is 10 mm in width, 10 mm in depth, and 0.2 mm in thickness. The semiconductor element 22 is a silicon IGBT (Insulated Gate Bipolar Transistor), and the size of the semiconductor element 22 is 10 mm in width, 10 mm in depth, and 0.2 mm in thickness.

[0016] As shown in Fig. 1, the case 51 is made of PPS (Polyphenylenesulfide) resin and is formed in a rectangular shape when viewed from above. The size of the case 51 is 70 mm wide, 100 mm deep, and 10 mm high. The case 51 covers the insulating substrate 10 and the semiconductor elements 21 and 22. The inside of the case 51 is filled with a potting sealing resin 52, which insulates and protects the semiconductor elements 21 and 22 and the insulating substrate 10 housed therein. The potting sealing resin 52 is made of epoxy resin with silica filler or the like dispersed therein.

[0017] 5, a copper main terminal 61 (plate thickness 0.64 mm) and a copper signal terminal 62 (plate thickness 0.64 mm) are formed integrally with the case 51 by insert molding. One end side of the main terminal 61 and the signal terminal 62 protrudes from the case 51, and the other end side of the main terminal 61 and the signal terminal 62 are covered by the case 51.

[0018] The upper surface main electrodes (not shown) of the semiconductor elements 21, 22 are connected to the other end of the main terminal 61 by solder 30, and the signal electrode (not shown) of the semiconductor element 22 is connected to the other end of the signal terminal 62 by an aluminum wire 40 (thickness 0.15 mm). In the case 51, the semiconductor elements 21, 22 are joined to the other end of the main terminal 61 to form a main terminal circuit. Here, the main terminal 61 corresponds to a plate-shaped electrode material. The power module section 1 is required to include at least one insulating substrate 10; for example, a 2-in-1 circuit is formed by one insulating substrate 10, and a 6-in-1 circuit is formed by three insulating substrates 10.

[0019] The lower surface (the other surface) of insulating substrate 10 is exposed from case 51 and is joined to the upper surface of base portion 72 of fin base 70 by solder 30. Fin base 70 is made of copper, and the surface of fin base 70 is nickel plated. Fin base 70 has base portion 72 and a plurality of fins 71. Base portion 72 has dimensions of 90 mm in width, 105 mm in depth, and 3 mm in thickness.

[0020] As shown in Figs. 1 to 5, the base portion 72 is formed in a rectangular and flat shape in top view, and is joined to the lower surface of the insulating substrate 10 by solder 30. The width of the base portion 72 is formed to be longer than the width of the case 51, and the outer periphery of the base portion 72 in the width direction protrudes toward the outer periphery side beyond the case 51. On the other hand, the depth of the base portion 72 is formed to be approximately the same length as the depth of the case 51, and the outer periphery of the base portion 72 in the depth direction protrudes toward the outer periphery side slightly beyond the case 51. The multiple fins 71 are fins for heat dissipation, and protrude downward (the opposite side of the insulating substrate 10 in the base portion 72) from the part of the lower surface of the base portion 72 excluding the outer periphery. The multiple fins 71 are arranged in a matrix at equal intervals, and the size of each fin 71 is 1.5 mm in diameter and 8 mm in height.

[0021] Next, the water-cooled jacket 74 will be described. As shown in Figs. 1 to 5, the water-cooled jacket 74 is made of aluminum and is formed in a rectangular shape when viewed from above. The size of the water-cooled jacket 74 is 120 mm wide, 150 mm deep, and 9 mm thick. A recess 76 that is recessed downward is provided in a portion of the water-cooled jacket 74 excluding the outer periphery. The recess 76 accommodates the fin base 70 via an adapter 73. A nozzle 75i through which cooling water is introduced and a nozzle 75o that discharges the cooling water that has flowed through the water-cooled jacket 74 are provided on two mutually opposing front and rear side surfaces of the four side surfaces of the water-cooled jacket 74.

[0022] Next, the adapter 73 will be described. As shown in Figs. 1 to 5, the adapter 73 is formed into a rectangular frame shape when viewed from above. The adapter 73 is disposed between the fin base 70 and the water-cooled jacket 74, and has the function of connecting the fin base 70 and the water-cooled jacket 74. Specifically, the adapter 73 is fastened to the fin base 70 using screws 81, and is also fastened to the water-cooled jacket 74 using screws 81. The adapter 73 is made of aluminum, and the size of the adapter 73 is 120 mm wide, 150 mm deep, and 9 mm thick.

[0023] The adapter 73 has a plate-shaped portion 730 and a protruding portion 731. The plate-shaped portion 730 is formed in a rectangular frame shape in a top view, and constitutes the outer periphery of the adapter 73. The protruding portion 731 is provided on the inner periphery side of the plate-shaped portion 730, and protrudes downward in the same direction as the direction in which the multiple fins 71 of the fin base 70 protrude so as to form a step with respect to the plate-shaped portion 730. An opening 732 that is rectangular in a top view is provided on the inner periphery side of the protruding portion 731 for accommodating the multiple fins 71. The base portion 72 of the fin base 70 is attached to the upper surface of the protruding portion 731, and the multiple fins 71 are accommodated in the opening 732, so that the protruding portion 731 surrounds the sides of the multiple fins 71.

[0024] The height of the step between the plate-shaped portion 730 and the protruding portion 731 is 2 mm. The depth of the recess 76 in the water-cooled jacket 74 is 6 mm, that is, the water-cooled jacket 74 is designed to accommodate a case in which the height of the multiple fins 71 is 6 mm. However, by fixing the fin base 70 at a high position via the adapter 73, the tips of the multiple fins 71, which are 8 mm high, come into contact with the bottom surface of the water-cooled jacket 74.

[0025] A watertight structure is formed by fastening the fin base 70 and the adapter 73, and the adapter 73 and the water-cooling jacket 74 with silicone O-rings 80 placed between them using screws 81. Grooves 733, 734 (see FIG. 6) are formed in the portion of the adapter 73 where the O-ring 80 is placed.

[0026] 2 and 4, an inlet portion 731i and an outlet portion 731o are provided on a side surface of the protruding portion 731 of the adapter 73 as flow straightening portions for straightening the flow of the cooling water flowing inside the water-cooling jacket 74. The inlet portion 739i has the same diameter as the opening diameter (φ5 mm) of the nozzle 75i of the water-cooling jacket 74 and is provided at a position corresponding to the nozzle 75i. The outlet portion 739o has the same diameter as the opening diameter (φ5 mm) of the nozzle 75o and is offset 2 mm upward (closer to the base portion 72 of the fin base 70) with respect to the nozzle 75o.

[0027] In the vicinity of the inlet portion 739i where the temperature of the cooling water is low, the cooling efficiency is reduced by applying cooling water with a high flow rate to the tips of the multiple fins 71, and as the temperature of the cooling water approaches the outlet portion 739o where the temperature of the cooling water is high, the cooling efficiency is increased by applying cooling water with a high flow rate to the bases of the multiple fins 71. In this manner, adjustment is made so that the entire multiple fins 71 are at the same temperature.

[0028] In a normal power module, the circuit formation of the main electrodes on the upper surfaces of the semiconductor elements 21, 22 is often performed by wire bonding. By forming the circuit using the main terminal 61 as a plate-shaped electrode material as in the power module 202 according to the first embodiment, it becomes possible to increase the current density and reduce the size of the semiconductor elements 21, 22 (chip shrink), and the power module 202 can be made more compact. On the other hand, the heat generation density increases, so higher cooling efficiency is required. Therefore, in the first embodiment, the height of the multiple fins 71 is increased and the flow of the cooling water is finely controlled.

[0029] <Power module manufacturing method> Next, a brief description will be given of a method for manufacturing the power module 202. Figures 6 to 8 are cross-sectional views showing the method for manufacturing the power module 202 according to the first embodiment.

[0030] 6, the O-ring 80 is fitted between the fin base 70 joined to the power module unit 1 and the adapter 73. Specifically, the O-ring 80 is placed in the groove 733 provided on the upper surface of the protruding portion 731 of the adapter 73.

[0031] Next, as shown in Fig. 7, the fin base 70 and the adapter 73 are fastened together using the screws 81. Finally, as shown in Fig. 8, with the O-ring 80 placed in the groove 734 provided on the underside of the plate-shaped portion 730 of the adapter 73, the adapter 73 and the water-cooling jacket 74 are fastened together using the screws 81.

[0032] <Effects> As described above, the power module 202 according to the first embodiment includes one power module unit 1 having an insulating substrate 10, semiconductor elements 21 and 22 mounted on the upper surface, which is one surface of the insulating substrate, a base portion 72 joined to the lower surface, which is the other surface of the insulating substrate 10, with solder 30, and a fin base 70 including a plurality of fins 71 protruding from the base portion 72 to the side opposite the insulating substrate 10, a case 51 covering the insulating substrate 10 and the semiconductor elements 21 and 22, a water-cooled jacket 74 having a recess 76 for accommodating the fin base 70, and an adaptor 73 disposed between the fin base 70 and the water-cooled jacket 74 and connecting the fin base 70 and the water-cooled jacket 74. The outer periphery of the adaptor 73 protrudes outward from the base portion 72 of the fin base 70.

[0033] Therefore, the adapter 73 is disposed between the fin base 70 and the water-cooled jacket 74, and the fin base 70 and the water-cooled jacket 74 are connected via the adapter 73, so that it is not necessary to make the base portion 72 of the fin base 70 protrude significantly toward the outer periphery in order to attach the fin base 70 to the water-cooled jacket 74. Since the amount of protrusion of the base portion 72 can be reduced, it is possible to reduce the thermal energy required to bond the lower surface of the insulating substrate 10 and the base portion 72, and it is possible to shorten the time required for heating and cooling. This improves the productivity of the power module 202.

[0034] In addition, since the fin base 70 and the water-cooled jacket 74 are connected via the adapter 73, it is possible to attach a high-density, small-sized power module unit 1 to a water-cooled jacket 74 designed to match a large-sized power module unit 1.

[0035] Furthermore, by making the fin base 70 smaller, the number that can be obtained per metal plate from which the fin base 70 is made increases, and the manufacturing cost of the fin base 70 decreases.

[0036] The adapter 73 also has a plate-shaped portion 730 including an outer periphery, and a protruding portion 731 that is provided on the inner periphery of the plate-shaped portion 730 and protrudes in the same direction as the multiple fins 71 of the fin base 70 protrudes, surrounding the sides of the multiple fins 71, and an inlet portion 739i and an outlet portion 739o are provided on the side of the protruding portion 731 as flow straightening portions for straightening the cooling water flowing within the water-cooled jacket 74.

[0037] Therefore, when arranging multiple fins 71 that are longer than those designed for a normal water-cooled jacket, the entire fin base 70 can exhibit uniform cooling performance by controlling the flow rate of the cooling water according to the position of the cooling water flow path.

[0038] It also includes a main terminal 61 as a plate-shaped electrode material having one end protruding from the case 51 and the other end covered by the case 51, and within the case 51, the semiconductor elements 21, 22 are joined to the other end of the main terminal 61 to form a main terminal circuit.

[0039] Therefore, compared to a case where a main terminal circuit is formed using wire bonding, it is possible to achieve a high current density in the power module section 1 and to make the module smaller.

[0040] Furthermore, since the base portion 72 of the fin base 70 and the plate-shaped portion 730 of the adapter 73 are fastened with screws, the connection between the fin base 70 and the adapter 73 can be performed in a process at room temperature.

[0041] <Modification of the first embodiment> Next, modified examples 1 and 2 of the first embodiment will be described with reference to Fig. 9 and Fig. 10. Fig. 9 is a cross-sectional view of a power module 202A according to modified example 1 of the first embodiment. Fig. 10 is a cross-sectional view of a power module 202B according to modified example 2 of the first embodiment. Figs. 9 and 10 correspond to Fig. 3.

[0042] In the first embodiment, the base portion 72 of the fin base 70 and the plate-shaped portion 730 of the adapter 73 are fastened with screws, but as shown in Fig. 9, in the first modification of the first embodiment, they are joined with a watertight adhesive 82. Also, no O-ring 80 is disposed between the fin base 70 and the adapter 73. By using the watertight adhesive 82 to fasten the fin base 70 and the adapter 73, the amount of protrusion of the base portion 72 required to apply the adhesive 82 can be made smaller than in the case of fastening with screws. This allows the fin base 70 to be further miniaturized.

[0043] The adhesive 82 may be made of epoxy or silicone, etc., as long as it can adhere to both metal and resin, and there are more options for materials than in the case of screw fastening. Also, by using an adhesive that can adhere at room temperature, such as a UV-curable type, as the adhesive 82, it is possible to suppress warping of the base part 72 compared to when it is cured at a high temperature.

[0044] Next, as shown in Fig. 10, in the second modification of the first embodiment, the base portion 72 of the fin base 70 and the plate-shaped portion 730 of the adapter 73 are joined by a joint 721 (welded). In addition, an O-ring 80 is not disposed between the fin base 70 and the adapter 73. By forming the joint 721 using friction rotation welding to fix the fin base 70 and the adapter 73, the protrusion amount of the base portion 72 required for welding can be made smaller than in the case of screw fastening or adhesive application. This allows the fin base 70 to be further miniaturized.

[0045] The joint 721 can also be formed by laser welding or the like. The fin base 70 and the adapter 73 can be joined by friction stir welding or laser welding not only when the materials are both metal but also when the adapter 73 is made of resin.

[0046] <Embodiment 2> Next, a power module 202C according to embodiment 2 will be described. Fig. 11 is a top view of the power module 202C according to embodiment 2. Note that in embodiment 2, the same components as those described in embodiment 1 are denoted by the same reference numerals, and the description thereof will be omitted.

[0047] 11, in the second embodiment, the power module 202C includes two power module sections 1, and although not shown, two recesses 76 are provided in the water-cooled jacket 74. In addition, although not shown, two openings 732 are also provided in the adapter 73.

[0048] Among electric vehicles, in the case of a one-motor BEV (Battery Electric Vehicle), one power module unit 1 is often sufficient, but in the case of a front-wheel drive vehicle with two motors, two power module units are required to control them separately. Also, in the case of an HEV (Hybrid Electric Vehicle), charging the battery with electricity generated by the internal combustion engine and motor control may be performed separately, and in this case too, two power module units 1 are required. For this reason, it was difficult to share the water-cooled jacket 74, but by using this adapter 73, it becomes possible to share the water-cooled jacket 74. Furthermore, depending on the difference in motor output between the front and rear wheels, power module units 1 with different dimensions may be used, and the water-cooled jacket 74 can be shared even when different grades of the same vehicle model are used.

[0049] In the second embodiment, two power module units 1 are mounted, but it is also possible to mount three or more. In this case, this can be realized by providing the recesses 76 of the water-cooling jacket 74 and the openings 732 of the adapter 73 according to the number of power module units 1. Also, for the connection between the base unit 72 of the fin base 70 and the plate-shaped unit 730 of the adapter 73, the structures of the first and second modifications of the first embodiment can be adopted.

[0050] <Modifications of the first and second embodiments> Next, a modification of the first and second embodiments will be described.

[0051] In the above, copper is used as the material for the fin base 70, but the same effect can be obtained by using aluminum partially plated with nickel as the material.

[0052] Although aluminum is used as the material for the adapter 73, the same effect can be obtained by using nickel-plated copper or a watertight resin (fiber-reinforced resin) as the material. Fiber-reinforced resin desirably has a thermal expansion coefficient similar to that of metal, between 10 ppm / K and 30 ppm / K. Furthermore, by manufacturing the adapter 73 from a metal that is less noble than the surface material of the fin base 70 (a metal with a high ionization tendency), corrosion caused by the cooling water is preferentially concentrated on the adapter 73, slowing down the corrosion of the fin base 70 and ensuring reliability.

[0053] Although the semiconductor elements 21 and 22 have been described as being made of silicon, the same effect can be obtained by using wide band gap semiconductors such as silicon carbide or gallium nitride for the semiconductor elements 21 and 22.

[0054] Although solder 30 made of 96.5% tin, 3% silver, and 0.5% copper with a melting point of 217° C. was used, the same effect can be obtained by using solder made of 99.3% tin and 0.7% copper with a melting point of 224° C. In addition, the same effect can be obtained by replacing the solder 30 that joins the semiconductor elements 21, 22 and the insulating substrate 10 with a silver sintered material or brazing material that has better heat resistance than solder.

[0055] Although an aluminum wire is used as the wire 40, the same effect can be obtained by using a wire made of an aluminum alloy containing a small amount of additive such as iron or a wire made of copper.

[0056] Although an epoxy resin with silica filler dispersed therein is used as the potting sealing resin 52, a filler such as alumina may be used instead of the silica filler, and the same effect can be obtained by mixing a silicone resin with an epoxy resin or by using a silicone gel.

[0057] Although the circuit is formed using the copper main terminal 61, the same effect can be obtained by forming the circuit using aluminum or aluminum alloy wire or ribbon.

[0058] In the above, a case-type module in which potting sealing resin 52 is injected into case 51 is used as power module 1, but the same effect can be obtained with a transfer mold-type module in which sealing resin is molded onto fin base 70.

[0059] It is desirable that the gap between the protrusion 731 of the adapter 73 and the water-cooled jacket 74 be smaller than the fin spacing of the fins 71 of the fin base 70, but if it is smaller than about 200% of the fin spacing, it is possible to prevent the cooling water from concentrating in the gap and reducing the cooling efficiency.

[0060] <Embodiment 3> In this embodiment, the power modules according to the above-mentioned embodiments 1 and 2 are applied to a power conversion device. Although the application of the power modules according to the embodiments 1 and 2 is not limited to a specific power conversion device, the following will describe, as embodiment 3, a case in which the power modules according to the embodiments 1 and 2 are applied to a three-phase inverter.

[0061] FIG. 12 is a block diagram showing a configuration of a power conversion system to which a power conversion device 200 according to the third embodiment is applied.

[0062] The power conversion system shown in Fig. 12 is composed of a power source 100, a power conversion device 200, and a load 300. The power source 100 is a DC power source and supplies DC power to the power conversion device 200. The power source 100 can be composed of various things, for example, a DC system, a solar cell, or a storage battery, or it may be composed of a rectifier circuit connected to an AC system or an AC / DC converter. The power source 100 may also be composed of a DC / DC converter that converts DC power output from a DC system into a predetermined power.

[0063] The power conversion device 200 is a three-phase inverter connected between the power source 100 and the load 300, converts DC power supplied from the power source 100 into AC power, and supplies the AC power to the load 300. As shown in Fig. 12, the power conversion device 200 includes a main conversion circuit 201 that converts DC power into AC power and outputs it, and a control circuit 203 that outputs a control signal for controlling the main conversion circuit 201 to the main conversion circuit 201.

[0064] The load 300 is a three-phase motor driven by AC power supplied from the power conversion device 200. The load 300 is not limited to a specific use, but is a motor mounted on various electric devices, and is used as, for example, a motor for a hybrid car, an electric car, a railroad car, an elevator, or an air conditioner.

[0065] The power conversion device 200 will be described in detail below. The main conversion circuit 201 includes a switching element (not shown) and a free wheel diode (not shown), and converts DC power supplied from the power source 100 into AC power by switching the switching element, and supplies the AC power to the load 300. There are various specific circuit configurations of the main conversion circuit 201, but the main conversion circuit 201 according to this embodiment is a two-level three-phase full bridge circuit, and can be configured with six switching elements and six free wheel diodes connected in reverse parallel to each switching element. A power module 202 is applied to at least one of the switching elements and free wheel diodes of the main conversion circuit 201. The power module 202 corresponds to the power module according to any one of the above-mentioned embodiments 1 and 2. The six switching elements are connected in series with two switching elements to form upper and lower arms, and each upper and lower arm forms each phase (U phase, V phase, W phase) of the full bridge circuit. The output terminals of each upper and lower arm, i.e., the three output terminals of the main conversion circuit 201, are connected to the load 300.

[0066] The main conversion circuit 201 also includes a drive circuit (not shown) for driving each switching element, but the drive circuit may be built in the power module 202, or the drive circuit may be provided separately from the power module 202. The drive circuit generates drive signals for driving the switching elements of the main conversion circuit 201 and supplies them to the control electrodes of the switching elements of the main conversion circuit 201. Specifically, in accordance with a control signal from a control circuit 203 (described later), the drive circuit outputs to the control electrodes of each switching element a drive signal for turning the switching element on and a drive signal for turning the switching element off. When maintaining a switching element in the on state, the drive signal is a voltage signal (on signal) equal to or higher than the threshold voltage of the switching element, and when maintaining a switching element in the off state, the drive signal is a voltage signal (off signal) equal to or lower than the threshold voltage of the switching element.

[0067] The control circuit 203 controls the switching elements of the main conversion circuit 201 so that a desired power is supplied to the load 300. Specifically, the control circuit 203 calculates the time (on time) for each switching element of the main conversion circuit 201 to be in the on state based on the power to be supplied to the load 300. For example, the main conversion circuit 201 can be controlled by PWM control that modulates the on time of the switching elements according to the voltage to be output. Then, a control command (control signal) is output to a drive circuit provided in the main conversion circuit 201 so that an on signal is output to a switching element that should be in the on state at each time point, and an off signal is output to a switching element that should be in the off state. The drive circuit outputs an on signal or an off signal as a drive signal to the control electrode of each switching element according to this control signal.

[0068] In the power conversion device 200 according to the present embodiment, the power modules according to the first and second embodiments are applied as the switching elements and free wheel diodes of the main conversion circuit 201, so that it is possible to realize improvement in productivity.

[0069] In the present embodiment, an example in which the power modules according to the first and second embodiments are applied to a two-level three-phase inverter has been described, but the application of the power modules according to the first and second embodiments is not limited to this, and the power modules can be applied to various power conversion devices. In the present embodiment, the power conversion device is a two-level power conversion device, but it may be a three-level or multilevel power conversion device, and when power is supplied to a single-phase load, the power modules according to the first and second embodiments may be applied to a single-phase inverter. Also, when power is supplied to a DC load or the like, the power modules according to the first and second embodiments can be applied to a DC / DC converter or an AC / DC converter.

[0070] Furthermore, the power conversion device to which the power modules according to the first and second embodiments are applied is not limited to the case where the load described above is an electric motor, but can also be used, for example, as a power supply device for an electric discharge machine, a laser processing machine, an induction heating cooker, or a non-contact power supply system, and can also be used as a power conditioner for a solar power generation system, a power storage system, or the like.

[0071] It should be noted that the embodiments can be freely combined, and each embodiment can be modified or omitted as appropriate.

[0072] Various aspects of the present disclosure are summarized below as appendices.

[0073] (Appendix 1) at least one power module unit including an insulating substrate, a semiconductor element mounted on one surface of the insulating substrate, a base portion joined to the other surface of the insulating substrate by soldering, a fin base including a plurality of fins protruding from the base portion to a side opposite the insulating substrate, and a case covering the insulating substrate and the semiconductor element; a water-cooled jacket having at least one recess for receiving the fin base; an adapter disposed between the fin base and the water-cooling jacket and connecting the fin base and the water-cooling jacket; A power module, wherein an outer periphery of the adapter protrudes outer periphery beyond the base portion of the fin base.

[0074] (Appendix 2) the adapter has a plate-like portion including the outer circumferential portion, and a protruding portion provided on an inner circumferential side of the plate-like portion, protruding in the same direction as the protruding direction of the plurality of fins of the fin base, and surrounding the sides of the plurality of fins; 2. The power module according to claim 1, wherein a straightening portion is provided on a side surface of the protrusion for straightening the cooling water flowing within the water-cooled jacket.

[0075] (Appendix 3) 3. The power module of claim 1 or 2, wherein at least a surface of the adapter is covered with a metal that is less noble than a surface material of the fin base.

[0076] (Appendix 4) The housing further includes a plate-shaped electrode material having one end protruding from the case and the other end covered by the case, 4. The power module according to claim 1, wherein a main terminal circuit is formed in the case by joining the semiconductor element to the other end side of the plate-shaped electrode material.

[0077] (Appendix 5) 3. The power module of claim 2, wherein the base portion of the fin base and the plate-shaped portion of the adapter are fastened by screws.

[0078] (Appendix 6) 3. The power module of claim 2, wherein the base portion of the fin base and the plate portion of the adapter are joined by an adhesive.

[0079] (Appendix 7) 3. The power module of claim 2, wherein the base portion of the fin base and the plate portion of the adapter are joined by welding.

[0080] (Appendix 8) The power module unit includes two of the power modules. 8. The power module according to claim 1, wherein the water-cooling jacket has two recesses.

[0081] (Appendix 9) A main conversion circuit having the power module according to any one of Supplementary Note 1 to Supplementary Note 8, which converts input power and outputs the converted power; a control circuit that outputs a control signal for controlling the main conversion circuit to the main conversion circuit; A power conversion device comprising: [Explanation of symbols]

[0082] 1 power module portion, 10 insulating substrate, 21, 22 semiconductor element, 51 case, 61 main terminal, 70 fin base, 71 fin, 72 base portion, 73 adapter, 74 water-cooled jacket, 76 recess, 200 power conversion device, 201 main conversion circuit, 202, 202A, 202B, 202C power modules, 203 control circuit, 730 plate-shaped portion, 731 protruding portion, 739i, 739o rectification portion.

Claims

1. at least one power module unit including an insulating substrate, a semiconductor element mounted on one surface of the insulating substrate, a fin base including a base portion joined to the other surface of the insulating substrate by solder and a plurality of fins protruding from the base portion to a side opposite to the insulating substrate, and a case covering the insulating substrate and the semiconductor element; a water-cooled jacket having at least one recess for receiving the fin base; an adapter disposed between the fin base and the water-cooling jacket and connecting the fin base and the water-cooling jacket; A power module, wherein an outer periphery of the adapter protrudes outer periphery beyond the base portion of the fin base.

2. the adapter has a plate-like portion including the outer circumferential portion, and a protruding portion provided on an inner circumferential side of the plate-like portion, protruding in the same direction as the protruding direction of the plurality of fins of the fin base, and surrounding the sides of the plurality of fins; The power module according to claim 1 , wherein a flow straightening portion is provided on a side surface of the protruding portion for straightening the flow of the cooling water flowing inside the water-cooling jacket.

3. The power module according to claim 1 , wherein at least a surface of the adapter is covered with a metal that is less noble than a surface material of the fin base.

4. The housing further includes a plate-shaped electrode material having one end protruding from the case and the other end covered by the case, 2. The power module according to claim 1, wherein a main terminal circuit is formed in the case by joining the semiconductor element to the other end side of the plate electrode material.

5. The power module according to claim 2 , wherein the base portion of the fin base and the plate-shaped portion of the adapter are fastened together with screws.

6. The power module according to claim 2 , wherein the base portion of the fin base and the plate-shaped portion of the adapter are joined by an adhesive.

7. The power module according to claim 2 , wherein the base portion of the fin base and the plate-shaped portion of the adapter are joined by welding.

8. The power module unit includes two of the power modules. The power module according to claim 1 , wherein the water-cooling jacket has two recesses.

9. A main conversion circuit having the power module according to claim 1, which converts input power and outputs the converted power; a control circuit that outputs a control signal for controlling the main conversion circuit to the main conversion circuit; A power conversion device comprising:

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