Power Conversion Equipment

Abstract

To provide a power conversion device that can achieve both cost reduction and high reliability.SOLUTION: In a power conversion device, a main circuit unit 11 comprises: a plurality of circuit bodies (an IGBT lead package 26T and a diode lead package 26D) each having a semiconductor element; and a printed board 25 that is mounted with the plurality of circuit bodies and has relay wiring 28M, DC wiring 28D, and AC wiring 28A for connecting between the plurality of circuit bodies. At least one of the AC wiring 28A and the DC wiring 28D is connected with a conductor member 101.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a power conversion device. [Background technology]

[0002] As background art to the present invention, the following Patent Document 1 describes a technology in which, in order to suppress heat generation in a semiconductor device, an auxiliary board is joined to a printed circuit board that forms the inverter circuit wiring, and the front and back of the auxiliary board are connected by through vias. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-137343 Summary of the Invention [Problem to be solved by the invention]

[0004] Based on the configuration of Patent Document 1, the present invention aims to provide a power conversion device that achieves both low cost and reliability in order to reduce wiring heat generation in a printed circuit board at even lower cost and improve the drivable current value. [Means for solving the problem]

[0005] The power conversion device of the present invention comprises a plurality of circuit bodies each having a semiconductor element, and a printed circuit board on which the plurality of circuit bodies are mounted and which has relay wiring, DC wiring, and AC wiring connecting the plurality of circuit bodies, and at least one of the AC wiring and the DC wiring is connected to a conductor member. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a power conversion device that achieves both low cost and high reliability. [Brief explanation of the drawings]

[0007] [Figure 1] Overall perspective view of inverter [Figure 2] Overall perspective view of the inverter after the cover is opened [Figure 3] A perspective cutaway view of line AA in Figure 2 [Figure 4] Cross section AA of Figure 2 [Figure 5] Exploded view of the main circuit unit and cooling water channels [Figure 6] Perspective view of the main circuit unit [Figure 7] A perspective view of the main circuit unit without the sealing resin [Figure 8] FIG. 1 is a cutaway perspective view of a main circuit unit, omitting the sealing resin, according to an embodiment of the present invention; [Figure 9] Exploded perspective view of lead package [Figure 10] 8 illustrating the connection between the lead package and the main circuit of the printed circuit board according to one embodiment of the present invention. [Figure 11] FIG. 11 is a diagram of a circuit body that connects the lead package of FIG. 10 and the main circuit of the printed circuit board and has a cooling water channel. [Figure 12] Modification of Figure 11 [Figure 13] Circuit diagram after connecting the lead package and printed circuit board

[0008] Hereinafter, an embodiment 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 some omissions and simplifications have been made as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0010] (Overall configuration of one embodiment of the present invention) FIG. 1 is a perspective view of the entire inverter.

[0011] The inside of the inverter housing 1 is sealed with a lid 2, and the cooling water passages and inverter components described below are built into the inside of the housing 1. An AC connector 3 and a DC connector 4 protrude from the inverter housing 1, and a signal connector 5 is output from the lid 2.

[0012] Fig. 2 is an overall perspective view of the inverter after the cover is opened, Fig. 3 is a cutaway perspective view taken along line AA in Fig. 2, and Fig. 4 is a cross-sectional view taken along line AA in Fig. 2.

[0013] A motor control board 6, a gate drive board 7, a smoothing capacitor 8, an EMC filter 9, a cooling water passage 10, and a main circuit unit 11 are arranged inside the inverter housing 1. The motor control board 6 is mounted on the top of the housing 1 so as to cover the gate drive board 7, the cooling water passage 10, and the main circuit unit 11. A signal connector 5 is mounted on the motor control board 6, and as described above, it penetrates the cover 2 and protrudes to the outside.

[0014] Board joining pins 12 are mounted on the gate drive board 7 (see FIG. 4). The board joining pins 12 are electrically connected to board joining through holes 22 (see FIG. 6) of the main circuit unit 11 by a joining material such as solder. The main circuit unit 11 is fixed by being sandwiched between cooling water channels 10 from above and below the plane of the drawing.

[0015] Fig. 5 is an exploded view of the main circuit unit and the cooling water passages, Fig. 6 is a perspective view of the main circuit unit, and Fig. 7 is a perspective view of the main circuit unit without the sealing resin.

[0016] The fixing holes 24 are used to fasten the main circuit unit 11 by sandwiching both sides of the main circuit unit 11 with the cooling water channel 10 using a method such as screwing. The cooling water channel 10 cools the power semiconductor elements mounted in a plurality of lead packages 26 in the main circuit unit 11 and the main circuit wiring of each part.

[0017] The main circuit unit 11 is configured by mounting multiple lead packages 26 on a printed circuit board 25 and sealing the entire assembly with sealing resin 14. An AC connection section 20 and a DC connection section 21 are formed on the printed circuit board 25, and are electrically connected to AC bus bars and DC bus bars, respectively, by screw fastening. In addition, the gate drive board 7 and smoothing capacitor 8 are electrically connected to board bonding through-holes 22 and capacitor bonding through-holes 23, respectively, by bonding materials such as solder.

[0018] The AC wiring exposed portion 50A, the relay wiring exposed portion 50M, the DC wiring exposed portion 50D, and the conductor member 101 shown in FIG. 7 will be described in detail later with reference to FIG.

[0019] Fig. 8 is a cutaway perspective view of a main circuit unit omitting the sealing resin according to one embodiment of the present invention, and Fig. 9 is an exploded perspective view of a lead package.

[0020] The lead package 26 includes an IGBT lead package 26T and a diode lead package 26D, which are circuit bodies, and are inserted into through holes 27 formed in the printed circuit board 25. Connection portions 30, 31 provided on the IGBT lead package 26T and the diode lead package 26D, respectively, are electrically connected by solder or the like to respective connection portions of the printed circuit board 25, which will be described later. In this manner, the circuit bodies are connected to each other on the printed circuit board 25, and the wiring between the main circuit unit 11 and the printed circuit board 25 is integrated.

[0021] In the lead packages 26T and 26D, the first lead frame 32 and the second lead frame 33, which are conductors, are electrically joined so as to sandwich the electrodes on both sides of the IGBT element 41 or the diode element 42. The lead frame 33 of the IGBT lead package 26T and the lead frame 32 of the diode lead package 26D are provided with base electrodes 34 for connection to the surface electrodes of the respective elements 41 and 42 while maintaining an insulating distance, and are connected to the IGBT element 41 and the diode element 42, respectively, during electrical joining.

[0022] The first connection portions 30 provided at both ends of the first lead frame 32 are electrically joined to protrusions 27a (described later) provided inside the through holes 27. The second connection portions 31 provided on the second lead frame 33 are connected to the surface wiring of the printed circuit board 25 to form main circuit wiring.

[0023] The snubber capacitor 40 is connected to the positive and negative wirings provided on the printed circuit board 25, and supplies a transient current during switching.

[0024] FIG. 10 is a cross-sectional view taken along CC in FIG. 8, illustrating the connection between the lead package and the main circuit of the printed circuit board according to one embodiment of the present invention.

[0025] 10 is composed of an IGBT element, a diode element, a first lead frame 32, and a second lead frame 33. Printed circuit board 25 is composed of through-holes 27, AC wiring 28A, relay wiring 28M, and DC wiring 28D.

[0026] Substrate layers are added to the front and back surfaces (surfaces in the vertical direction on the page) of printed circuit board 25, and AC wiring 28A, relay wiring 28M, and DC wiring 28D are exposed on the surface of printed circuit board 25 to form exposed wiring portions 50A, 50M, and 50D. In addition, a back surface substrate layer 52 is formed on the surface of printed circuit board 25 opposite to the surface on which exposed wiring portions 50A, 50M, and 50D are formed.

[0027] The AC wiring 28A is configured by laminating two layers of wiring members in the thickness direction of the printed circuit board 25. Note that the configuration is not limited to two layers, and multiple layers may be laminated in the thickness direction of the printed circuit board 25. The AC wiring exposed portion 50A is a portion of the AC wiring 28A exposed from the printed circuit board 25, and a conductor member 101 is joined to the exposed portion 50A via a joining member 102 such as solder.

[0028] The DC wiring 28D has a structure in which positive and negative wiring are laminated. The DC wiring exposed portion 50D (the portion of the DC wiring 28D exposed from the printed circuit board 25) connected to the DC wiring 28D has a conductor member 101 joined thereto via a joining member 102 such as solder, similar to the AC wiring exposed portion 50A. Although not shown, a configuration in which the conductor member 101 is further joined to the relay wiring exposed portion 50M via a joining member 102 such as solder may also be employed. This reduces the wiring resistance of the board wiring and ensures insulation in the back substrate layer formed on the side of the printed circuit board 25 opposite the surface on which the circuit body is mounted.

[0029] Furthermore, the AC wiring exposed portion 50A, the relay wiring exposed portion 50M, and the DC wiring exposed portion 50D are electrically connected to the AC wiring 28A, the relay wiring 28M, and the DC wiring 28D via through vias 29.

[0030] The effect of mounting and connecting conductor member 101 to exposed wiring portions 50A, 50M, and 50D will be described. For example, AC wiring 28A is a portion of the circuit body where current heat generation concentrates. When driving a large current exceeding 500 Arms, the temperature rises due to wiring heat generation. If the temperature exceeds the heat resistance temperature of printed circuit board 25, the reliability of the device may decrease. Therefore, by mounting and connecting additional conductor member 101 to the portion of the surface of printed circuit board 25 where AC wiring 28A (exposed wiring portion 50A) is located, the wiring resistance can be reduced, the drivable current value can be increased, and wiring heat generation can be reduced. Similarly, by mounting and connecting additional conductor member 101 to DC wiring 28D (exposed wiring portion 50D) on the surface of printed circuit board 25, the wiring resistance can be further reduced, the drivable current value can be further increased, and wiring heat generation can be further reduced.

[0031] Note that the object of the present invention can be expected to be achieved even if the conductor member 101 is mounted and connected to only either the AC wiring exposed portion 50A or the DC wiring exposed portion 50D. Furthermore, the effect of the present invention can be further improved by mounting and connecting the conductor member 101 not only to the AC wiring exposed portion 50A and the DC wiring exposed portion 50D but also to the relay wiring exposed portion 50M, but depending on the design, it is also possible to omit mounting and connecting the conductor member 101 to the relay wiring exposed portion 50M.

[0032] Moreover, the conductor member 101 is formed of a carbon fiber material or an alloy material (metal) such as a copper alloy or an aluminum alloy, which has excellent thermal conductivity in the planar direction, thereby achieving a reduction in wiring heat generation due to the improved thermal conductivity of the conductor member 101. Furthermore, the AC wiring 28A and the DC wiring 28D have a laminated structure, which reduces inductance.

[0033] The first connection portion 30 of the first lead frame 32 and the protrusion 27a in the through hole 27 are electrically connected by solder or the like, and at the same time, the second connection portion 31 of the second lead frame 33 and the board surface wiring 50M are electrically connected by solder or the like. In this manner, the circuit bodies are connected to each other on the printed circuit board 25 and are integrated with the wiring of the printed circuit board 25. Although not shown, the signal pads of the IGBT elements 41 are electrically connected to the signal wiring formed on the surface of the printed circuit board 25 by wire bonding or the like.

[0034] Furthermore, in the present invention, a configuration has been described in which the conductor member 101 is mounted and connected to the surface wiring on the mounting side of the circuit body in the printed circuit board 25, but it is also possible to mount and connect an additional conductor member 101 on the back substrate layer 52 to improve the effect.

[0035] FIG. 11 is a diagram of a circuit body that connects the lead package of FIG. 10 and the main circuit of the printed circuit board and has a cooling water passage.

[0036] Each component of the circuit body is fixed with sealing resin 14, and the AC wiring and DC wiring of the circuit body are in contact with heat dissipation protrusions 201 formed on the housing portion of the cooling water channel 10 via heat conductive insulating sheets 200. This allows heat generated in the AC wiring and DC wiring to be dissipated to the cooling water channel 10 via the heat dissipation protrusions 201.

[0037] FIG. 12 is a modification of FIG.

[0038] The back substrate layer 52 (see FIG. 10) and the first lead frames 32 of the respective circuit bodies form a back flat surface 53 on the back surface (the lower side of the drawing) of the printed circuit board 25. The back flat surface 53 is in contact with the cooling water channel 10 via the heat dissipation adhesive member 202. This flat surface structure facilitates the connection between the water channel 10, the heat dissipation adhesive member 202, and the thermally conductive insulating sheet 200, and simplifies the process.

[0039] FIG. 13 is a circuit diagram after the lead package and the printed circuit board are connected.

[0040] By connecting the lead package 26 and the printed circuit board 25, an upper and lower arm half circuit 60 is formed, which is made up of the IGBT 41 and the diode 42 of each pair of arms.

[0041] As described above, according to the present invention, it is possible to improve the drive current in the main circuit unit 11 provided in the power conversion device. Furthermore, since the drivable current value can be improved without changing the size of the printed circuit board or the wiring thickness, low costs can be achieved.

[0042] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0043] (1) The power conversion device includes a plurality of circuit bodies each having a semiconductor element, and a printed circuit board 25 on which the plurality of circuit bodies are mounted and which has relay wiring 28M, DC wiring 28D, and AC wiring 28A connecting the plurality of circuit bodies together, and at least one of AC wiring 28A and DC wiring 28D is connected to conductor member 101. In this way, a power conversion device that achieves both low cost and high reliability can be provided.

[0044] (2) The AC wiring 28A and the DC wiring 28D are in contact with the cooling water channel 10 or the heat dissipation protrusions 201 formed on the cooling water channel 10 via the insulating sheet 200. In this way, heat generated in the AC wiring 28A and the DC wiring 28D can be dissipated to the cooling water channel 10 via the heat dissipation protrusions 201.

[0045] (3) AC wiring 28A, relay wiring 28M, and DC wiring 28D are formed so as to be exposed on the front and back surfaces of printed circuit board 25, respectively, and each wiring on the front surface and each wiring on the back surface are electrically connected via through vias 29. In this way, when circuit bodies are connected to each other, they can be integrated with the wiring of printed circuit board 25.

[0046] (4) The relay wiring 28M is connected to the conductive member 101. This reduces the wiring resistance, improves the drivable current value, and reduces wiring heat generation.

[0047] (5) The plurality of circuit bodies are respectively arranged in a plurality of through holes 27 formed in the printed circuit board 25 and mounted on the printed circuit board 25, and a flat surface 53 is formed by the back surface of the printed circuit board 25 and the surface of the plurality of circuit bodies that passes through the through holes 27, and the flat surface 53 is in contact with the cooling water channel 10 via the heat dissipation adhesive 202. This facilitates the connection between the water channel 10, the heat dissipation adhesive 202, and the thermally conductive insulating sheet 200, and simplifies the process.

[0048] (6) The conductor member 101 is made of a carbon fiber material or an alloy material, which improves the thermal conductivity of the conductor member 101, thereby reducing heat generation in the wiring.

[0049] The present invention is not limited to the above-described embodiments, and various modifications and combinations of other configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiments, and includes those in which some of the configurations are omitted. [Explanation of symbols]

[0050] 1 Inverter housing 2 Lid 3 AC connector 4 DC connectors 5 Signal Connector 6 Motor control board 7 Gate drive board 8 smoothing capacitors 9 EMC Filters 10 Cooling channel 11 Main circuit unit 12 PCB connecting pins 13 Upper and lower arms 14 Sealing resin 20 AC connection 21 DC connection 22 PCB bonding through holes 23 Capacitor junction through hole 24 fixing hole 25 Printed Circuit Board 26 lead package 26T IGBT lead package 26D Diode Lead Package 27 Through hole 27a Protrusion 28A AC wiring 28M relay wiring 28D DC wiring 29 Through Vias 30 First connection part 31 Second connection part 32 First lead frame 33 Second lead frame 34 Pedestal electrode 40 snubber capacitor 41 IGBT element 42 Diode element 50A AC wiring exposed part 50M Exposed relay wiring 50D DC wiring exposed part 52 Backside PCB layer 53 Back flat surface 59 Exposed lead surface 60 Upper and lower arm half circuit 70 Conductor member addition part 101 (Carbon-based) Conductor Materials 102 (Carbon-based) Conductor Joint 200 Thermally conductive insulating sheet 201 Heat radiation protrusion 202 Heat dissipation adhesive material

Claims

1. A plurality of circuit bodies each having a semiconductor element; a printed circuit board on which a plurality of the circuit bodies are mounted, the printed circuit board having relay wiring, DC wiring, and AC wiring that connect the plurality of the circuit bodies to each other; the circuit body includes a first lead package and a second lead package; the first lead package includes a first lead frame electrically connected to the DC wiring in the printed circuit board, and a second lead frame electrically connected to the relay wiring in the printed circuit board; the second lead package has a third lead frame electrically connected to the AC wiring of the printed circuit board and a fourth lead frame electrically connected to the relay wiring of the printed circuit board, the AC wiring, the relay wiring, and the DC wiring are formed and exposed on the front and back surfaces of the printed circuit board, respectively; the front surface and the rear surface of the AC wiring, the relay wiring, and the DC wiring are electrically connected to each other via a plurality of through vias; At least one of the AC wiring and the DC wiring is connected to a conductor member; The conductor member is not electrically connected to anything other than the printed circuit board, and is mounted so as to cover at least one of the front surface and the back surface in a portion where the plurality of through vias are formed in the AC wiring and the DC wiring. Power conversion equipment.

2. The power conversion device according to claim 1, the AC wiring and the DC wiring are in contact with a heat dissipation protrusion formed on the cooling water channel or an outer surface of a housing of the cooling water channel via an insulating sheet; The heat dissipation protrusion is at least partially overlapped with the conductive member in the stacking direction. Power conversion equipment.

3. The power conversion device according to claim 1, The conductive member is connected to the relay wiring. Power conversion equipment.

4. The power conversion device according to claim 1, the plurality of circuit bodies are mounted on the printed circuit board by being disposed in a plurality of through holes formed in the printed circuit board, a flat surface is formed by a rear surface of the printed circuit board and surfaces of the plurality of circuit bodies that pass through the through holes of the first lead frame and the third lead frame, The flat surface is in contact with the cooling water passage via a heat dissipation adhesive. Power conversion equipment.

5. The power conversion device according to claim 1, The conductive member is made of a carbon fiber material or an alloy material. Power conversion equipment.

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