JP2024164408A - Power Conversion Equipment - Google Patents

Abstract

To provide a power conversion device that has achieved size reduction and cost lowering, and enhanced productivity while reducing the number of components.SOLUTION: A power conversion device comprises: a transformer having a transformer core that forms a magnetic circuit, and a plurality of transformer coils each provided with a transformer winding part wound around the transformer core; and a reactor having a reactor core that forms a magnetic circuit, and one or a plurality of reactor coils each provided with a reactor winding part wound around the reactor core. Each of the transformer winding part and the reactor winding part is formed into a planar shape that curves on a flat surface. One transformer coil and one reactor coil are disposed side by side and made into an integrated coil member which is electrically and mechanically combined by an integration part.SELECTED DRAWING: Figure 5

Description

This application relates to a power conversion device.

Due to recent environmental regulations and technological advances surrounding automobiles, electric vehicles or hybrid vehicles of various sizes have been developed and are becoming more and more popular. Electric vehicles that use a motor as a drive source, such as hybrid vehicles or electric vehicles, are equipped with multiple power conversion devices. A power conversion device is a device that converts an input current from DC to AC, AC to DC, or converts an input voltage into a different voltage. Specific examples of power conversion devices installed in electric vehicles include a charger that converts commercial AC power into DC power to charge a high-voltage battery, a DC/DC converter that converts the DC power of the high-voltage battery into DC power of a different voltage, and an inverter that converts the DC power from the high-voltage battery into AC power for the motor.

DC/DC converters are installed in electric vehicles, for example, to charge a low-voltage lead battery from a high-voltage lithium-ion battery. To protect the surroundings from high voltage, the high-voltage lithium-ion battery is insulated from the chassis and low-voltage system. In DC/DC converters, insulation between the high-voltage input side and the low-voltage output side is generally required by a transformer. In DC/DC converters, the DC input voltage is switched using semiconductor elements, etc., converted into an AC signal, etc., and input to the primary side of the transformer. The output from the secondary side of the transformer is rectified using semiconductor elements, etc., smoothed by a smoothing reactor, and then output from the DC/DC converter as a DC output voltage.

Insulated DC/DC converters mounted on electric vehicles or hybrid vehicles are generally of the kW class or higher. As a result, transformers and smoothing reactors have become larger and are more likely to generate heat. In power conversion devices, the coils used in these transformers and reactors are made of sheet metal, which increases the cross-sectional area of the coil to reduce losses and improves heat dissipation, thereby reducing the temperature rise of the coil. A configuration for connecting a secondary coil of a transformer made of sheet metal to a reactor coil has been disclosed (see, for example, Patent Document 1). In Patent Document 1, a connecting member such as a bus bar is provided between the secondary coil of the transformer and the reactor coil, and the coil and bus bar are fixed with a fixing member such as a screw to connect the two coils.

Patent No. 6987196

The secondary coil of a transformer and the reactor coil can be connected using a connecting member such as a bus bar. However, when connecting coils to each other using a connecting member such as a bus bar and a fixing member such as a screw, the number of parts increases due to the addition of the connecting and fixing members, which creates an issue of increased manufacturing costs for the power conversion device. Furthermore, when connecting the coil and bus bar with a fixing member, screws and nuts are required, which increases the number of parts, and it is necessary to provide space for the screws and nuts, which increases the number of parts in the power conversion device, increases the size, and increases the manufacturing costs.

Therefore, the present application aims to obtain a power conversion device that is smaller, less expensive, and more productive while reducing the number of parts.

The power conversion device disclosed in the present application includes a transformer having a transformer core forming a magnetic circuit and a plurality of transformer coils each having a transformer winding portion wound around the transformer core, and a reactor having a reactor core forming a magnetic circuit and a single or multiple reactor coils each having a reactor winding portion wound around the reactor core, where each of the transformer winding portion and the reactor winding portion is formed into a curved plate shape on a plane, and one transformer coil and one reactor coil are arranged side by side and are electrically and mechanically connected by an integration portion to form an integrated coil member.

According to the power conversion device disclosed in the present application, a transformer having a transformer core forming a magnetic circuit and a plurality of transformer coils provided with a transformer winding part wound around the transformer core, a reactor core forming a magnetic circuit, and a reactor having a single or a plurality of reactor coils provided with a reactor winding part wound around the reactor core, each of which is formed in a curved plate shape on a plane, and one transformer coil and one reactor coil are arranged side by side and are an integrated coil member electrically and mechanically connected by an integrated part, so that one transformer coil and one reactor coil can be connected without using a connecting member such as a bus bar and a fixing member such as a screw, thereby reducing the number of parts of the connecting member and the fixing member. Since the connecting member and the fixing member are not necessary and the space for arranging the connecting member and the fixing member is reduced, the power conversion device can be made smaller and less expensive. Since the assembly process of the power conversion device using the fixing member is reduced, the productivity of the power conversion device can be improved. The number of coil components is reduced, making it possible to make the power conversion device smaller and less expensive.

1 is a perspective view showing an outline of a power conversion device according to a first embodiment; 1 is a plan view showing an outline of a power conversion device according to a first embodiment; 2 is an exploded perspective view showing an outline of a transformer coil and a reactor coil of the power conversion device according to the first embodiment; FIG. 1 is a diagram showing a circuit configuration of a power conversion device according to a first embodiment; 1 is a plan view showing an outline of a main part of a power conversion device according to a first embodiment. 1 is a plan view showing an outline of a main part of a power conversion device according to a first embodiment. 3 is a cross-sectional view of a main part of the power conversion device taken along the line AA in FIG. 2. 3 is a cross-sectional view of a main part of the power conversion device taken along the line BB in FIG. 2. 10 is a plan view showing an outline of a main part of another power conversion device according to the first embodiment. FIG. 11 is a cross-sectional view showing an outline of a power conversion device according to a second embodiment. FIG. 11 is a cross-sectional view showing an outline of a power conversion device according to a third embodiment. FIG. FIG. 13 is a plan view showing an outline of a power conversion device according to a fourth embodiment. 13 is a plan view showing an outline of a main part of a power conversion device according to a fifth embodiment. FIG.

The power conversion device according to the embodiment of the present application will be described below with reference to the drawings. Note that the same or equivalent members and parts in each drawing will be denoted by the same reference numerals.

Embodiment 1.
FIG. 1 is a perspective view showing an outline of a power conversion device 100 according to a first embodiment, FIG. 2 is a plan view showing an outline of the power conversion device 100, FIG. 3 is an exploded perspective view showing an outline of a transformer coil 71 and a reactor coil 3 of the power conversion device 100, FIG. 4 is a diagram showing a circuit configuration of the power conversion device 100, FIG. 5 is a plan view showing an outline of a main part of the power conversion device 100, showing a transformer core 20 and a part of the reactor core 21, and an integrated coil member 10, and FIG. 6 is a plan view showing an outline of a main part of the power conversion device 100, showing the transformer core 20 and a part of the reactor core 21, and an integrated coil member 10. FIG. 7 is a cross-sectional view of the main part of the power conversion device 100 taken along the A-A cross section in FIG. 2, showing the transformer 70, the reactor 80, the first heat dissipation member 32, and the housing 50, omitting the resin case 40; FIG. 8 is a cross-sectional view of the main part of the power conversion device 100 taken along the B-B cross section in FIG. 2, showing the transformer 70, the reactor 80, the first heat dissipation member 32, the second heat dissipation member 33, and the housing 50, omitting the resin case 40. The power conversion device 100 is a DC/DC converter that converts the DC voltage of a DC power source 95 into a secondary DC voltage insulated by a transformer 70 and outputs the DC voltage to a load such as a battery. The power conversion device 100 is not limited to a DC/DC converter.

<Power conversion device 100>
An example of the main circuit configuration of the power conversion device 100 will be described with reference to Fig. 4. In Fig. 4, the left side is the input side and the right side is the output side. A DC power supply 95 is connected to the input side of the power conversion device 100, and a load (not shown) such as a low-voltage battery is connected to the output side. In this embodiment, the specific configuration of the transformer 70 and the reactor 80 shown in Fig. 4 will be described as the power conversion device 100, but the power conversion device 100 may be configured to include a rectifier diode 60a, a semiconductor switching element 61a, and a smoothing capacitor 90. The power conversion device 100 includes a semiconductor module 61 connected to a DC power supply 95, having a plurality of semiconductor switching elements 61a, and configured as a full bridge circuit that converts an input DC voltage into an AC voltage and outputs the converted voltage, an insulated transformer 70 that converts the voltage of the AC power output from the semiconductor module 61 and outputs the converted voltage, a diode module 60 having a rectifier diode 60a that rectifies the output of the transformer 70, and a reactor 80 and a smoothing capacitor 90 that smooth the output of the transformer 70. The output of the transformer 70 is output to a load via a reactor 80 and a smoothing capacitor 90 .

The semiconductor module 61 has a plurality of semiconductor switching elements 61a that constitute a full bridge circuit. In this embodiment, the semiconductor module 61 has four semiconductor switching elements, but the number of semiconductor switching elements is not limited to this. The semiconductor switching elements are, for example, MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) with diodes built in between the source and drain. The semiconductor switching elements are not limited to MOSFETs, and may be self-extinguishing semiconductor switching elements such as IGBTs (Insulated Gate Bipolar Transistors) with diodes connected in reverse parallel. The semiconductor switching elements are formed on a semiconductor substrate made of a semiconductor material such as silicon (Si), silicon carbide (SiC), or gallium nitride (GaN).

The transformer 70 has a transformer primary coil 1 and a transformer secondary coil 2. The transformer secondary coil 2 has a center tap section 6. The center tap section 6 is connected to the reactor 80.

The diode module 60 has rectifier diodes 60a, which are rectifier elements made of semiconductor elements. The ends of the transformer secondary coil 2 of the transformer 70 other than the center tap section 6 are each connected to the rectifier diodes 60a. In this embodiment, there are two rectifier diodes 60a, each shown as a single diode, but two or more diodes connected in parallel may also be used. In addition, a self-extinguishing semiconductor switching element such as a MOSFET may also be used as the rectifier element.

<Transformer 70, Reactor 80>
The configurations of the transformer 70 and the reactor 80, which are essential parts of the present application, will be described. As shown in FIG. 7, the power conversion device 100 includes a transformer 70 having a transformer core 20 forming a magnetic circuit and a plurality of transformer coils 71 each having a transformer winding portion 4 wound around the transformer core 20, and a reactor core 21 forming a magnetic circuit and a reactor 80 having a single or multiple reactor coils 3 each having a reactor winding portion 5 wound around the reactor core 21. In this embodiment, as shown in FIG. 3, the transformer coil 71 has a transformer primary coil 1 which is a high-voltage coil and a transformer secondary coil 2 which is a low-voltage coil. Each of the transformer winding portion 4 and the reactor winding portion 5 is formed into a plate shape curved on a plane. As shown in FIG. 8, one transformer coil and one reactor coil are arranged side by side and are electrically and mechanically connected to each other by an integrated portion 10a to form an integrated coil member 10. In the integrated coil member 10 , one transformer coil portion is a transformer secondary coil portion 12 , and one reactor coil portion is a reactor coil portion 13 .

By configuring in this manner, the transformer secondary coil section 12 and the reactor coil section 13 can be connected without using connecting members such as bus bars and fixing members such as screws, thereby reducing the number of connecting and fixing members. Since connecting and fixing members are not required and the space required for arranging the connecting and fixing members is reduced, the power conversion device 100 can be made smaller and less expensive. Since the assembly process of the power conversion device 100 using fixing members is reduced, the productivity of the power conversion device 100 can be improved. Since the number of coil components is reduced, the power conversion device 100 can be made smaller and less expensive.

In this embodiment, as shown in FIG. 1, the transformer coil 71 and the reactor coil 3 are integrated with a resin member to form a resin case 40 that houses the transformer coil 71 and the reactor coil 3. The integration with the resin member is performed, for example, by integral molding. With this configuration, insulation between each coil is easily ensured and the distance between each coil can be reduced. Since the distance between each coil is reduced, the power conversion device 100 can be made smaller.

In this embodiment, the power conversion device 100 includes a housing 50 having a cooling surface 51 for cooling the transformer 70 and the reactor 80. As shown in FIG. 7, the bottom surface of the transformer core 20 and the bottom surface of the reactor core 21 are thermally connected to the core mounting surface 52, which is the cooling surface 51 consisting of the same plane. By configuring in this manner, the transformer 70 and the reactor 80 can be efficiently cooled by the same surface of the housing 50. Since the transformer 70 and the reactor 80 are cooled by the same surface of the housing 50, the power conversion device 100 can be made smaller. In addition, since the number of processing surfaces of the housing 50 with different heights can be reduced, the workability of the housing 50 can be improved. In addition, the dimensional tolerance between the housing 50 and each coil can be reduced, and the heat dissipation of each coil can be improved, so that the power conversion device 100 can be made smaller and less expensive. In this embodiment, a first heat dissipation member 32 is provided between the bottom surface of the transformer core 20 and the core mounting surface 52 and between the bottom surface of the reactor core 21 and the core mounting surface 52. This configuration allows the transformer 70 and reactor 80 to be cooled even more efficiently.

As shown in FIG. 1, the resin case 40 is fixed to the housing 50 by a fixing member 31. The transformer core 20 and the reactor core 21 are fixed to the housing 50 by a spring 30. Details of each member and the configuration of the power conversion device 100 are described below.

First, the transformer core 20 and the reactor core 21 will be described. The transformer core 20 is made of, for example, ferrite. As shown in FIG. 7, the transformer core 20 is divided into an E shape, and has an annular outer core and a columnar central core 20a that connects two opposing parts of the outer core. The central core 20a is a part of the transformer core 20 around which the transformer winding section 4 is wound. In this embodiment, the transformer primary coil 1a, the transformer secondary coil 2a, and the transformer winding section 4 of the transformer secondary coil section 12 of the integrated coil member 10 are wound around the central core 20a. Of the divided transformer cores 20, the bottom surface of the transformer core 20 provided on the housing 50 side is thermally connected to the housing 50 via the first heat dissipation member 32. In this embodiment, as shown in FIG. 5, the transformer core 20 and the reactor core 21 are divided into an E shape, but this is not limited thereto, and they may be divided into an E shape and an I shape, an I shape and a U shape, or a U shape and a U shape, etc. FIG. 9 shows an example in which the transformer core 20 and the reactor core 21 are divided into a U shape. In FIG. 9, the transformer core 20 and the reactor core 21 are not disposed between the transformer winding section 4 and the reactor winding section 5. By configuring in this way, the length of the integrated section 10a of the integrated coil member 10 is reduced, so that the power conversion device 100 can be made smaller and less expensive.

In addition, in this embodiment, the transformer core 20 is thermally connected to the housing 50 via the first heat dissipation member 32, but this is not limited thereto. If the temperature of the transformer core 20 is a usable temperature without using the first heat dissipation member 32, the transformer core 20 and the housing 50 may be thermally connected without the first heat dissipation member 32. By thermally connecting the transformer core 20 and the housing 50 without using the first heat dissipation member 32, the first heat dissipation member 32 is eliminated, and the cost of the power conversion device 100 can be reduced.

The reactor core 21 is made of, for example, ferrite. As shown in FIG. 7, the reactor core 21 is divided into an E-shape and has an annular outer core and a columnar central core 21a that connects two opposing parts of the outer core. The central core 21a is a part of the reactor core 21 around which the reactor winding section 5 is wound. In this embodiment, the reactor coil 3a and the reactor coil section 13 of the integrated coil member 10 are wound around the central core 21a. Of the divided reactor cores 21, the bottom surface of the reactor core 21 provided on the housing 50 side is thermally connected to the housing 50 via the first heat dissipation member 32. In this embodiment, the reactor core 21 is divided into an E-shape, but this is not limited thereto, and it may be divided into an E-shape and an I-shape, an I-shape and a U-shape, or a U-shape and a U-shape.

In addition, in the present embodiment, the reactor core 21 is thermally connected to the housing 50 via the first heat dissipation member 32, but the present invention is not limited thereto. When the temperature of the reactor core 21 is a usable temperature without using the first heat dissipation member 32, the reactor core 21 and the housing 50 may be thermally connected without the first heat dissipation member 32. By thermally connecting the reactor core 21 and the housing 50 without the first heat dissipation member 32, the first heat dissipation member 32 is reduced, and the cost of the power conversion device 100 can be reduced. In addition, in the present embodiment, each of the divided parts of the divided reactor core 21 is configured to abut against each other, but the present invention is not limited thereto. In order to change characteristics such as an inductance value or a DC superposition characteristic, a gap may be provided without abutting the divided parts of the divided reactor core 21.
The material of the reactor core 21 is not limited to ferrite, but may be other core materials such as a dust core.

Next, the transformer coil 71 and the reactor coil 3 will be described. As shown in FIG. 3, the transformer coil 71 has two transformer primary coils 1a, a transformer secondary coil 2a, and a transformer secondary coil section 12 as multiple transformer coils. The two transformer primary coils 1a form the transformer primary coil 1, and the transformer secondary coil 2a and the transformer secondary coil section 12 form the transformer secondary coil 2. The reactor coil 3 has a reactor coil 3a and a reactor coil section 13 as multiple reactor coils. The number of reactor coils 3 is not limited to multiple, and may be singular.

The transformer primary coil 1 is made of, for example, copper sheet metal. The transformer primary coil 1 has a transformer winding section 4 wound around the central core 20a of the transformer core 20. Two transformer primary coils 1a with different winding directions are stacked in a first extension direction (extension direction of the dashed arrow Z1 shown in FIG. 3), which is the extension direction of the central core 20a. Each end of the transformer primary coil 1a is a transformer primary interlayer connection section 14 provided inside the transformer winding section 4, and a transformer primary terminal 7 provided outside the transformer winding section 4. The transformer primary terminal 7 is a transformer terminal that extends from the end of the transformer winding section 4 and is connected to the outside. The transformer primary interlayer connection section 14 provided on each of the two transformer primary coils 1a is connected by, for example, welding. The number of turns of each of the transformer primary coils 1a is 3, and by connecting the transformer primary interlayer connection section 14, the number of turns of the transformer primary coil 1 becomes 6.

In this embodiment, the number of transformer primary coils 1a is two, but this is not limited to two and may be two or more. When configuring the transformer primary coil 1 with a number other than two, two of the total ends of the transformer primary coil 1a may be configured as transformer primary terminals 7 and the remaining may be configured as transformer primary interlayer connection parts 14, so that the winding direction of each connected layer is alternately different. The material of the transformer primary coil 1 is not limited to copper, and may be other sheet metal materials such as copper alloy, aluminum, and aluminum alloy.

The transformer secondary coil 2a and the transformer secondary coil section 12 of the integrated coil member 10 are made of, for example, copper sheet metal. The transformer secondary coil 2a and the transformer secondary coil section 12 have a transformer winding section 4 wound around the central core 20a of the transformer core 20. The transformer secondary coil 2a and the transformer secondary coil section 12, which have different winding directions, are stacked in a first extension direction (extension direction of dashed arrow Z1 shown in FIG. 3), which is the extension direction of the central core 20a. In this embodiment, the number of turns of each of the transformer secondary coil 2a and the transformer secondary coil section 12 is 1, so there appears to be no difference in the winding direction of the transformer secondary coil 2a and the transformer secondary coil section 12, but the direction of the current flowing therethrough is different.

The ends of the transformer secondary coil 2a and the transformer secondary coil section 12 are the transformer secondary terminal 8 and the center tap section 6, respectively. The transformer secondary terminal 8 is a transformer terminal that extends from the end of the transformer winding section 4 and is connected to the outside. The center tap section 6 is a section that connects the transformer secondary coil 2a and the transformer secondary coil section 12. The center tap sections 6 provided on the transformer secondary coil 2 and the transformer secondary coil section 12 are connected, for example, by welding.

The transformer secondary coil 2, which has a higher current on the low voltage side than the transformer primary coil 1, is configured to have a coil thickness, i.e., a sheet metal thickness, greater than that of the transformer primary coil 1, thereby reducing electrical resistance and thermal resistance and suppressing heat generation, so that the temperature of the transformer secondary coil 2 is a usable temperature. Although the transformer secondary coil 2 is configured with a center tap, the transformer secondary coil 2 is not limited to a center tap configuration. If the transformer secondary coil 2 and the reactor coil 3 are connected, the integrated coil member 10 can be applied, and the number and winding direction of the transformer secondary coil 2a can be changed according to the circuit configuration. In addition, in this embodiment, a configuration in which the transformer secondary coil 2a and the transformer secondary coil section 12 are stacked is shown, but depending on the circuit configuration, it may be configured with only the transformer secondary coil section 12. In addition, the material of the transformer secondary coil 2a and the transformer secondary coil section 12 is not limited to copper, and other sheet metal materials such as copper alloys, aluminum, and aluminum alloys may be used.

The reactor coil 3a and the reactor coil section 13 are made of, for example, copper sheet metal. The reactor coil 3a and the reactor coil section 13 have a reactor winding section 5 wound around the central core 21a of the reactor core 21. The reactor coils 3a and the reactor coil section 13 are stacked in the same winding direction in the second extension direction (the extension direction of the dashed arrow Z2 shown in FIG. 3), which is the extension direction of the central core 21a. The number of turns of each of the reactor coil 3a and the reactor coil section 13 is 1.

One end of the reactor coil 3a is a reactor terminal 9 that is connected to the outside, and the other end of the reactor coil 3a is a reactor interlayer connection part 15 that is connected to the reactor coil part 13. One end of the reactor coil part 13 is a connection part 13a that is connected to the center tap part 6 via the integrated part 10a, and the other end of the reactor coil part 13 is a reactor interlayer connection part 15 that is connected to the reactor coil 3a. The reactor interlayer connection parts 15 provided on the reactor coil 3a and the reactor coil part 13 are connected by, for example, welding.

In this embodiment, the total number of the reactor coils 3a and the reactor coil portions 13 is two, but the number may be other than two. For example, the reactor coil 3 may be only the reactor coil portion 13. In addition, when there is one integrated coil member 10 and the total number is other than two depending on the number of reactor coils 3a, one of the total ends of the reactor coils 3a may be the reactor terminal 9 and the other may be the reactor interlayer connection portion 15, and the winding direction may be the same in each connected layer. In addition, the material of the reactor coils 3a and the reactor coil portions 13 is not limited to copper, and may be other sheet metal materials such as copper alloy, aluminum, and aluminum alloy.

The integrated coil member 10 has a transformer secondary coil portion 12 and a reactor coil portion 13, and the center tap portion 6 of the transformer secondary coil portion 12 and the reactor coil portion 13 are connected to the connection portion 13a via an integrated portion 10a. The integrated portion 10a is made of the same sheet metal as the transformer secondary coil portion 12 and the reactor coil portion 13. In this embodiment, the integrated coil member 10 is made of a single sheet metal. By configuring in this manner, the transformer secondary coil portion 12 and the reactor coil portion 13 can be connected without using connecting members such as bus bars and fixing members such as screws, so that the number of parts of the connecting members and fixing members can be reduced. Since the connecting members and fixing members are not required and the space for arranging the connecting members and fixing members is reduced, the power conversion device 100 can be made smaller and less expensive. Since the assembly process of the power conversion device 100 using fixing members is reduced, the productivity of the power conversion device 100 can be improved. Because the number of coil components is reduced, the power conversion device 100 can be made smaller and less expensive. In addition, because the transformer secondary coil section 12 and the reactor coil section 13 can be simultaneously manufactured from a single sheet of metal, the productivity of the power conversion device 100 can be improved.

In this embodiment, the thickness of the integrated coil member 10 is the same on both the transformer coil side and the reactor coil side. By configuring it in this way, it is not necessary to prepare a transformer coil side portion and a reactor coil side portion having different thicknesses, so the productivity of the power conversion device 100 can be improved.

In the integrated coil member 10, the plate-shaped conductor width of the transformer winding section 4 and the plate-shaped conductor width of the reactor winding section 5 are different. Because the transformer winding section 4 and the reactor winding section 5 are formed in a plate shape, the conductor width can be easily changed between the transformer secondary coil section 12 and the reactor coil section 13. Therefore, even though it is an integrated coil member 10, the conductor width can be set to the minimum required without matching the required cross-sectional area of the transformer secondary coil section 12 or the reactor coil section 13, whichever is larger, and the power conversion device 100 can be made smaller and less expensive.

In this embodiment, a larger current flows through the transformer secondary coil 2, which is the low-voltage side coil, than through the transformer primary coil 1, which is the high-voltage side coil, and the transformer coil portion of the integrated coil member 10 is the low-voltage side coil. The transformer secondary coil 2 is prone to heat generation due to the large current flowing through it. By configuring it in this way, heat generated in the transformer secondary coil portion 12 of the integrated coil member 10 can be dissipated from the reactor coil portion 13 side of the integrated coil member 10, thereby suppressing heat generation in the transformer secondary coil portion 12.

In this embodiment, as shown in FIG. 8, the integrated coil member 10 is made of a single sheet metal having a bent portion 16 at the integrated portion 10a. The transformer winding portion 4 and the reactor winding portion 5 of the integrated coil member 10 are arranged parallel to the coil mounting surface 53 of the cooling surface 51. The transformer winding portion 4 of the integrated coil member 10 is arranged farther away from the coil mounting surface 53 of the cooling surface 51 than the reactor winding portion 5 of the integrated coil member 10. Another transformer winding portion 4 is arranged between the transformer winding portion 4 of the integrated coil member 10 and the coil mounting surface 53 of the cooling surface 51. The bent portion 16 is a portion for connecting the transformer secondary coil portion 12 and the reactor portion, which are at different distances from the coil mounting surface 53.

By configuring in this way, the bent portion 16 can easily change the distance from the coil mounting surface 53 of the transformer winding portion 4 and the reactor winding portion 5 in the integrated coil member 10. Another transformer winding portion 4 close to the coil mounting surface 53 is cooled by the coil mounting surface 53, and another transformer winding portion 4 away from the coil mounting surface 53 is cooled by dissipating heat to the reactor winding portion 5 close to the coil mounting surface 53. In this embodiment, the transformer coil portion of the integrated coil member 10 is the transformer secondary coil portion 12 of the low-voltage side coil that is prone to heat generation. Therefore, the heat of the transformer secondary coil portion 12 can be efficiently dissipated to the reactor winding portion 5 close to the coil mounting surface 53. In addition, by making the other transformer winding portion 4 close to the coil mounting surface 53 the transformer winding portion 4 of the transformer secondary coil 2a, the heat of the transformer secondary coil 2a can be efficiently dissipated to the coil mounting surface 53.

In this embodiment, the reactor winding portion 5 and the separate transformer winding portion 4 of the integrated coil member 10 are thermally connected to the coil mounting surface 53, which is the cooling surface 51, via the second heat dissipation member 33, which is a heat dissipation member. Each of the thermally connected portions of the reactor winding portion 5 and the separate transformer winding portion 4 of the integrated coil member 10 is exposed from the resin case 40. By configuring in this manner, the transformer secondary coil 2a and the reactor coil portion 13 can be efficiently cooled.

In this embodiment, the low-voltage coil and the high-voltage coil are alternately arranged along the first extension direction (extension direction of Z1), which is the extension direction of the central core 20a. As shown in FIG. 7, the arrangement of the stacked coils is in the order of the transformer secondary coil 2a, which is the low-voltage coil, the transformer primary coil 1a, which is the high-voltage coil, the transformer secondary coil part 12, which is the low-voltage coil, and the transformer primary coil 1a, which is the high-voltage coil, from the side of the core mounting surface 52 of the housing 50. By configuring in this way, it is possible to reduce the loss of the coil due to the skin effect, to reduce the temperature rise, and to reduce the required cross-sectional area of each coil. In addition, by arranging the transformer secondary coil 2a, which has a large coil cross-sectional area on the low-voltage side, on the side close to the housing 50, it is possible to reduce the voltage resistance specification and thickness of the second heat dissipation member 33. In addition, by dissipating the heat generated in the transformer primary coil 1a to the housing 50 via the transformer secondary coil 2a and the transformer secondary coil section 12, the temperature rise of the transformer primary coil 1 can be reduced, the required cross-sectional area of each coil can be reduced, and the power conversion device 100 can be made smaller and less expensive.

In this embodiment, the transformer coil 71 of the integrated coil member 10 is a low-voltage coil, and another low-voltage coil is arranged between the low-voltage coil of the integrated coil member 10 and the cooling surface 51. The arrangement of the coils is in the order of the transformer secondary coil 2a, which is a low-voltage coil, the transformer primary coil 1a, which is a high-voltage coil, the transformer secondary coil section 12, which is a low-voltage coil, and the transformer primary coil 1a, which is a high-voltage coil, from the cooling surface 51 side of the housing 50. By configuring in this way, the transformer secondary coil 2a, which is likely to generate heat, can be brought closer to the cooling surface 51, so that the transformer secondary coil 2a can efficiently dissipate heat. The heat of the transformer secondary coil section 12, which is likely to generate heat, can be dissipated to the reactor coil section 13 of the integrated coil member 10. Since the heat dissipation of the transformer secondary coil 2 is promoted, the required cross-sectional area of the transformer secondary coil 2 can be reduced, and the power conversion device 100 can be made smaller and less expensive.

In the reactor 80, the stacked coils are arranged in the order of the reactor coil 13 and the reactor coil 3a from the side of the core mounting surface 52 of the housing 50. With this configuration, the reactor coil 13 coupled to the transformer secondary coil 12, which is prone to heat generation, is arranged close to the cooling surface 51, so that the heat of the transformer secondary coil 12 is efficiently dissipated to the cooling surface 51, which is the core mounting surface 52, via the reactor coil 13. Since the heat dissipation of the transformer secondary coil 2 is further promoted, the required cross-sectional area of the transformer secondary coil 2 can be reduced, and the power conversion device 100 can be made smaller and less expensive.

Note that, if insulation and heat dissipation between the transformer primary coil 1a and the housing 50 can be ensured, the transformer primary coil 1a may be located closest to the housing 50. In addition, although the two transformer primary coils 1a and the transformer secondary coil 2 and transformer secondary coil section 12 are arranged alternately, this is not limiting, and if heat dissipation of these coils can be ensured, the stacking order may be changed.

In this embodiment, the transformer coil 71 portion of the integrated coil member 10 is the transformer secondary coil portion 12, which is a low-voltage coil, and the transformer secondary coil portion 12 is a center-tap type coil having a center tap portion 6, to which the integrated portion 10a is connected. With this configuration, the center tap portion 6 is the midpoint of the transformer secondary coil 2, and the heat of the transformer secondary coil 2 on both sides can be dissipated in a balanced manner from the integrated reactor coil portion 13 from the midpoint.

In this embodiment, one or both of the transformer coil 71 portion of the integrated coil member 10 and the reactor coil 3 portion of the integrated coil member 10 are thermally connected to the cooling surface 51 via a heat dissipation member. In the first embodiment, as shown in FIG. 8, the reactor coil portion 13, which is one of the transformer coil 71 portion of the integrated coil member 10 and the reactor coil 3 portion of the integrated coil member 10, is thermally connected to the coil mounting surface 53, which is the cooling surface 51, via the second heat dissipation member 33, which is a heat dissipation member. By configuring in this manner, the heat generated in the integrated coil member 10 can be efficiently dissipated to the coil mounting surface 53. The configuration in which both the transformer coil 71 portion of the integrated coil member 10 and the reactor coil 3 portion of the integrated coil member 10 are thermally connected to the cooling surface 51 via a heat dissipation member will be described later.

In this embodiment, as shown in FIG. 8, the first extension direction (Z1 extension direction) and the second extension direction (Z2 extension direction) are parallel, and the transformer 70 and the reactor 80 are arranged adjacent to each other in a direction perpendicular to the first extension direction and the second extension direction. With this configuration, the transformer secondary coil portion 12 and the reactor coil portion 13 of the integrated coil member 10 can be arranged close to each other, so that the integrated portion 10a of the integrated coil member 10 can be shortened. Since the integrated portion 10a is shortened, the integrated coil member 10 can be made smaller and less expensive, and heat generation of the integrated coil member 10 can be suppressed. In addition, the power conversion device 100 can be made smaller and less expensive.

In this embodiment, the transformer coil 71 has a transformer primary terminal 7 and a transformer secondary terminal 8 as transformer terminals connected to the outside, and the reactor coil 3 has a reactor terminal 9 connected to the outside, and the transformer primary terminal 7, the transformer secondary terminal 8, and the reactor terminal 9 are arranged on the same side as the adjacent transformer 70 and reactor 80 when viewed in the first extension direction. In FIG. 2, the direction perpendicular to the paper surface is the first extension direction, and the transformer primary terminal 7, the transformer secondary terminal 8, and the reactor terminal 9 are arranged on the lower side of the adjacent transformer 70 and reactor 80. By configuring in this way, the components connected to the transformer primary terminal 7, the transformer secondary terminal 8, and the reactor terminal 9 can be arranged side by side on the same side as the transformer 70 and the reactor 80, so that the size of the power conversion device 100 including the connected components can be reduced. In addition, the connected components can be arranged on the cooling surface 51 of the housing 50, so that the connected components can be cooled by the cooling surface 51.

Next, the resin case 40 will be described. The resin member forming the resin case 40 is, for example, polyphenylene sulfide resin. The transformer primary coil 1a, the transformer secondary coil 2a, the reactor coil 3a, and the integrated coil member 10 are integrally molded and fixed so that adjacent coils are insulated by a spatial distance or the resin case 40. As shown in FIG. 2, the resin case 40 is provided with a positioning wall 41 that restricts the position of the divided transformer core 20 and the divided reactor core 21 in the vertical direction relative to the stacking direction, and a positioning protrusion 42 that restricts the position of the resin case 40 and the housing 50. The position of the resin case 40 is determined by fitting the positioning protrusion 42 into a positioning hole 54 provided in the housing 50.

The resin case 40 is fixed to the housing 50 at a portion between the transformer coil 71 and the reactor coil 3. The portion where the resin case 40 is fixed to the housing 50 is the fixing portion 43. The resin case 40 is fixed to the housing 50 at the fixing portion 43 by a fixing member 31 such as a screw. In this embodiment, the resin case 40 has a plurality of fixing portions 43, and the fixing portions 43 are arranged at the four corners of the outer periphery of the resin case 40 in addition to the portion between the transformer coil 71 and the reactor coil 3. It is desirable to provide the fixing portion 43 at least in the portion between the transformer coil 71 and the reactor coil 3. By configuring in this manner, the resin case 40 can be stably fixed to the housing 50 with a small number of fixing portions. In addition, deformation of the resin case 40 is suppressed, and an increase in the thickness of the second heat dissipation member 33 is suppressed, so that the heat dissipation properties of the transformer coil 71 and the reactor coil 3 can be improved. Because the heat dissipation of the transformer coil 71 and reactor coil 3 is improved, the power conversion device 100 can be made smaller and less expensive.

In addition, instead of providing the resin case 40 with a positioning protrusion 42 that restricts the position with respect to the housing 50, a protrusion shape may be provided on the housing 50 side, and a hole shape that fits with the protrusion shape of the housing 50 may be provided on the resin case 40. In addition, the transformer primary coil 1a, the transformer secondary coil 2a, the reactor coil 3a, and the integrated coil member 10 are configured to be integrally molded, but this is not limited to this, and the transformer primary coil 1a, the transformer secondary coil 2a, the reactor coil 3a, and the integrated coil member 10 may be configured to be outsert-molded into the resin case 40. In addition, the resin member is not limited to polyphenylene sulfide resin, and other molding resin materials may be used. In addition, the location of the fixing portion 43 is not limited to the above-mentioned location, and the fixing portion 43 may be reduced depending on the vibration conditions required for the power conversion device 100, the presence or absence of the second heat dissipation member 33, and the type of the second heat dissipation member 33.

Next, the heat dissipation member will be described. The first heat dissipation member 32 and the second heat dissipation member 33 are, for example, heat dissipation sheets made of silicone. As shown in FIG. 7, the first heat dissipation member 32 is disposed between the transformer core 20 and the housing 50, and between the reactor core 21 and the housing 50. The spring 30 presses the transformer core 20 and the reactor core 21 against the housing 50, so that the first heat dissipation member 32 is pressed by the transformer core 20 and the reactor core 21. As shown in FIG. 8, the second heat dissipation member 33 is disposed between the part of the transformer secondary coil 2a exposed from the transformer core 20, the part of the reactor coil portion 13 exposed from the reactor core 21, and the integrated portion 10a on the side of the reactor coil portion 13 and the housing 50. By fixing the resin case 40 to the housing 50 with the fixing member 31, the second heat dissipation member 33 is pressed by the transformer secondary coil 2a, the reactor coil portion 13, and the integrated portion 10a.

The second heat dissipation member 33 is arranged on the side of the housing 50 of the transformer secondary coil 2a, the reactor coil portion 13, and the integrated portion 10a, but is not limited thereto. When the coil closest to the housing 50 is changed due to a change in the lamination configuration of each coil, it is desirable to arrange the second heat dissipation member 33 between the coil closest to the housing 50 and the housing 50. In addition, when a portion extending from a coil other than the coil closest to the housing 50 is used as a cooling portion, the second heat dissipation member 33 may be arranged between the cooling portion and the housing 50. In addition, the first heat dissipation member 32 and the second heat dissipation member 33 are not limited to heat dissipation sheets made of silicone, and may be grease, hardening grease, or adhesive. In addition, a filler or the like may be contained in the heat dissipation member to improve the heat dissipation and insulation properties of the heat dissipation member.

Next, the fixing member 31 and the spring 30 will be described. The fixing member 31 is, for example, a screw made of an iron alloy. Note that the material of the fixing member 31 is not limited to an iron alloy, but may be iron, an aluminum alloy, or a copper alloy. Furthermore, although the fixing member 31 is a screw, the material is not limited to an iron alloy, but may be a spring mechanism made of stainless steel, iron, an aluminum alloy, or a copper alloy.

The spring 30 is made of, for example, a sheet metal made of stainless steel. As shown in FIG. 1, one end of the spring 30 is fixed to the housing 50, and the other end abuts against the transformer core 20 or the reactor core 21. When the spring 30 abuts against the transformer core 20 or the reactor core 21, the spring 30 presses the transformer core 20 and the reactor core 21 toward the housing 50. When the transformer core 20 and the reactor core 21 are pressed toward the housing 50, the transformer core 20 and the reactor core 21 are fixed to the housing 50. In this embodiment, the power conversion device 100 has four springs 30, the transformer core 20 is fixed by two springs 30, and the reactor core 21 is fixed by two springs 30. The number of springs 30 is not limited to this, and the transformer core 20 and the reactor core 21 may be fixed by more springs 30.

Next, the housing 50 will be described. The housing 50 is made of, for example, an aluminum alloy by die casting. The material of the housing 50 is not limited to an aluminum alloy, and may be an aluminum or magnesium alloy. The housing 50 has a core mounting surface 52 and a coil mounting surface 53 as a cooling surface 51 for cooling the transformer 70 and the reactor 80. As shown in FIG. 8, the core mounting surface 52 and the coil mounting surface 53 are surfaces with different heights, and each is formed of the same plane. The bottom surface of the transformer core 20 and the bottom surface of the reactor core 21 are thermally connected to the core mounting surface 52 via the first heat dissipation member 32. The reactor winding portion 5 of the integrated coil member 10 and another transformer winding portion 4 are thermally connected to the coil mounting surface 53 via the second heat dissipation member 33. By changing the heights of the core mounting surface 52 and the coil mounting surface 53, the thermally connected parts can be effectively cooled without changing the configuration of the transformer 70 and the reactor 80.

The power conversion device 100 may also be provided with a cover that covers the components mounted on the cooling surface 51, along with the cooling surface 51. By providing a cover, each component mounted on the power conversion device 100 can be protected from foreign objects that may enter the power conversion device 100. If the cover is made of metal, the mounted components can be protected from electromagnetic noise. A cooling structure through which a refrigerant flows may also be provided on the surface of the housing 50 opposite the cooling surface 51. The refrigerant is, for example, cooling water. By providing a cooling structure, the heat generated from the transformer 70 and the reactor 80 can be cooled more efficiently.

As described above, the power conversion device 100 according to the first embodiment includes a transformer 70 having a transformer core 20 forming a magnetic circuit and a plurality of transformer coils 71 each having a transformer winding section 4 wound around the transformer core 20, and a reactor 80 having a reactor core 21 forming a magnetic circuit and a single or multiple reactor coils 3 each having a reactor winding section 5 wound around the reactor core 21. Each of the transformer winding section 4 and the reactor winding section 5 is formed in a curved plate shape on a plane, and one transformer coil and one reactor coil are arranged side by side and are electrically and mechanically connected to each other by an integrated section 10a to form an integrated coil member 10. Therefore, the transformer secondary coil section 12, which is one transformer coil, and the reactor coil section 13, which is one reactor coil, can be connected without using a connecting member such as a bus bar and a fixing member such as a screw, thereby reducing the number of parts for the connecting members and fixing members. Since no connecting members and fixing members are required and the space required for arranging the connecting members and fixing members is reduced, the power conversion device 100 can be made smaller and less expensive. Since the assembly process of the power conversion device 100 using fixing members is reduced, the productivity of the power conversion device 100 can be improved. Since the number of coil components is reduced, the power conversion device 100 can be made smaller and less expensive.

When the thickness of the integrated coil member 10 is the same on both the transformer coil side and the reactor coil side, there is no need to prepare a transformer coil side portion and a reactor coil side portion having different thicknesses, which improves the productivity of the power conversion device 100.

When the integrated coil member 10 is made of a single sheet of metal, the transformer secondary coil section 12 and the reactor coil section 13 can be connected without using connecting members such as bus bars and fixing members such as screws, so the number of connecting and fixing members can be reduced. Since connecting and fixing members are not required and the space required for arranging the connecting and fixing members is reduced, the power conversion device 100 can be made smaller and less expensive. Since the assembly process of the power conversion device 100 using fixing members is reduced, the productivity of the power conversion device 100 can be improved. In addition, the transformer secondary coil section 12 and the reactor coil section 13 can be manufactured simultaneously from a single sheet of metal, so the productivity of the power conversion device 100 can be improved.

When the plate-shaped conductor width of the transformer winding section 4 and the plate-shaped conductor width of the reactor winding section 5 in the integrated coil member 10 are different, the transformer winding section 4 and the reactor winding section 5 are formed in a plate shape, so that the conductor width can be easily changed between the transformer secondary coil section 12 and the reactor coil section 13. Therefore, even though it is an integrated coil member 10, the conductor width can be set to the minimum required without matching the required cross-sectional area of the transformer secondary coil section 12 or the reactor coil section 13, whichever is larger. Since the plate-shaped conductor width of the transformer winding section 4 and the plate-shaped conductor width of the reactor winding section 5 can be set to the minimum required conductor width, the power conversion device 100 can be made smaller and less expensive.

When the power conversion device 100 includes a housing 50 having a cooling surface 51 for cooling the transformer 70 and the reactor 80, and the bottom surface of the transformer core 20 and the bottom surface of the reactor core 21 are thermally connected to the core mounting surface 52, which is the cooling surface 51 consisting of the same plane, the transformer 70 and the reactor 80 can be efficiently cooled by the same surface of the housing 50. Since the transformer 70 and the reactor 80 are cooled by the same surface of the housing 50, the power conversion device 100 can be made smaller. In addition, since the number of processing surfaces of the housing 50 with different heights can be reduced, the workability of the housing 50 can be improved. In addition, since the dimensional tolerance between the housing 50 and each coil can be reduced and the heat dissipation of each coil can be improved, the power conversion device 100 can be made smaller and less expensive.

When the integrated coil member 10 is made of a single sheet metal having a bent portion 16 at the integrated portion 10a, the transformer winding portion 4 and the reactor winding portion 5 of the integrated coil member 10 are arranged parallel to the coil mounting surface 53 of the cooling surface 51, the transformer winding portion 4 of the integrated coil member 10 is arranged farther away from the coil mounting surface 53 of the cooling surface 51 than the reactor winding portion 5 of the integrated coil member 10, and another transformer winding portion 4 is arranged between the transformer winding portion 4 of the integrated coil member 10 and the coil mounting surface 53 of the cooling surface 51, the bent portion 16 can easily change the distance from the coil mounting surface 53 of the transformer winding portion 4 and the reactor winding portion 5 in the integrated coil member 10. The other transformer winding portion 4 close to the coil mounting surface 53 can be cooled by the coil mounting surface 53, and the other transformer winding portion 4 away from the coil mounting surface 53 can be cooled by heat dissipation to the reactor winding portion 5 close to the coil mounting surface 53. In addition, when the transformer coil portion of the integrated coil member 10 is the transformer secondary coil portion 12 of the low-voltage side coil that is prone to heat generation, the heat of the transformer secondary coil portion 12 can be efficiently dissipated to the reactor winding portion 5 close to the coil mounting surface 53. In addition, when another transformer winding portion 4 close to the coil mounting surface 53 is the transformer winding portion 4 of the transformer secondary coil 2a, the heat of the transformer secondary coil 2a can be efficiently dissipated to the coil mounting surface 53.

When the reactor winding portion 5 of the integrated coil member 10 and the separate transformer winding portion 4 are thermally connected to the coil mounting surface 53, which is the cooling surface 51, via the second heat dissipation member 33, which is a heat dissipation member, the transformer secondary coil 2a having the separate transformer winding portion 4 and the reactor winding portion 5 of the integrated coil member 10 can be efficiently cooled.

A larger current flows through the transformer secondary coil 2, which is the low-voltage side coil, than through the transformer primary coil 1, which is the high-voltage side coil. When the transformer coil portion of the integrated coil member 10 is the low-voltage side coil, heat generated in the transformer secondary coil portion 12 of the integrated coil member 10 can be dissipated from the reactor coil portion 13 side of the integrated coil member 10, thereby suppressing heat generation in the transformer secondary coil portion 12.

When the low-voltage coil and the high-voltage coil are arranged alternately along the first extension direction, which is the extension direction of the central core 20a, the loss of the coil can be reduced due to the skin effect, the temperature rise can be reduced, and the required cross-sectional area of each coil can be reduced. In addition, by arranging the transformer secondary coil 2a, which has a large coil cross-sectional area on the low-voltage side, on the side close to the housing 50, the voltage resistance specification and thickness of the second heat dissipation member 33 can be reduced. In addition, by dissipating the heat generated in the transformer primary coil 1a to the housing 50 via the transformer secondary coil 2a and the transformer secondary coil part 12, the temperature rise of the transformer primary coil 1 can be reduced, the required cross-sectional area of each coil can be reduced, and the power conversion device 100 can be made smaller and less expensive.

The transformer coil 71 portion of the integrated coil member 10 is a low-voltage coil. When another low-voltage coil is disposed between the low-voltage coil of the integrated coil member 10 and the cooling surface 51, the transformer secondary coil 2a, which is another low-voltage coil and is prone to heat generation, can be brought closer to the cooling surface 51 to efficiently dissipate heat from the transformer secondary coil 2a. The heat from the transformer secondary coil portion 12, which is prone to heat generation, can be dissipated to the reactor coil portion 13 of the integrated coil member 10. Since heat dissipation from the transformer secondary coil 2 is promoted, the required cross-sectional area of the transformer secondary coil 2 can be reduced, thereby enabling the power conversion device 100 to be made smaller and less expensive.

The transformer coil 71 portion of the integrated coil member 10 is the transformer secondary coil portion 12, which is the low-voltage side coil. The transformer secondary coil portion 12 is a center-tap type coil having a center tap portion 6. When the integrated portion 10a is connected to the center tap portion 6, the center tap portion 6 is the midpoint of the transformer secondary coil 2, so that the heat of the transformer secondary coil 2 on both sides can be dissipated in a balanced manner from the integrated reactor coil portion 13 from the midpoint.

When the transformer coil 71 and the reactor coil 3 are integrated with a resin member and a resin case 40 is formed to house the transformer coil 71 and the reactor coil 3, insulation between the coils is easily ensured and the distance between the coils can be reduced. Since the distance between the coils is reduced, the power conversion device 100 can be made smaller.

When the resin case 40 is fixed to the housing 50 at the portion between the transformer coil 71 and the reactor coil 3, the resin case 40 can be stably fixed to the housing 50 with a small number of fixing points. In addition, deformation of the resin case 40 is suppressed, and an increase in the thickness of the second heat dissipation member 33 is suppressed, so that the heat dissipation properties of the transformer coil 71 and the reactor coil 3 can be improved. Since the heat dissipation properties of the transformer coil 71 and the reactor coil 3 are improved, the power conversion device 100 can be made smaller and less expensive.

When one or both of the transformer coil 71 portion of the integrated coil member 10 and the reactor coil 3 portion of the integrated coil member 10 are thermally connected to the cooling surface 51 via a heat dissipation member, the heat generated in the integrated coil member 10 can be efficiently dissipated to the coil mounting surface 53.

When the first extension direction (Z1 extension direction) and the second extension direction (Z2 extension direction) are parallel and the transformer 70 and the reactor 80 are arranged adjacent to each other in a direction perpendicular to the first extension direction and the second extension direction, the transformer secondary coil portion 12 and the reactor coil portion 13 of the integrated coil member 10 can be arranged close to each other, so that the integrated portion 10a of the integrated coil member 10 can be shortened. Since the integrated portion 10a is shortened, the integrated coil member 10 can be made smaller and less expensive, and heat generation of the integrated coil member 10 can be suppressed. In addition, the power conversion device 100 can be made smaller and less expensive.

When the transformer coil 71 has a transformer primary terminal 7 and a transformer secondary terminal 8 as transformer terminals connected to the outside, and the reactor coil 3 has a reactor terminal 9 connected to the outside, and the transformer primary terminal 7, the transformer secondary terminal 8, and the reactor terminal 9 are arranged on the same side of the adjacent transformer 70 and reactor 80 when viewed in the first extension direction, the components connected to the transformer primary terminal 7, the transformer secondary terminal 8, and the reactor terminal 9 can be arranged side by side on the same side of the transformer 70 and the reactor 80, so that the size of the power conversion device 100 including the connected components can be reduced. In addition, the connected components can be arranged on the cooling surface 51 of the housing 50, so that the connected components can be cooled by the cooling surface 51.

Embodiment 2.
A power conversion device 100 according to embodiment 2 will be described. Fig. 10 is a cross-sectional view showing an outline of the power conversion device 100 according to embodiment 2, taken at the same position as in Fig. 8. In the power conversion device 100 according to embodiment 2, the configuration of the integrated coil member 10 is different from that of embodiment 1.

The integrated coil member 10 is made of a flat plate, and is thermally connected to the coil mounting surface 53, which is the cooling surface 51. In this embodiment, the integrated coil member 10 is thermally connected to the coil mounting surface 53 via the second heat dissipation member 33. In the first embodiment, the integrated coil member 10 has a bent portion 16 in the integrated portion 10a, but in this embodiment, the integrated portion 10a does not have the bent portion 16, and the integrated portion 10a is configured as a flat plate portion. In addition, the configuration of this embodiment is such that both the transformer coil 71 portion of the integrated coil member 10 and the reactor coil 3 portion of the integrated coil member 10 are thermally connected to the cooling surface 51 via the heat dissipation member. With this configuration, the integrated portion 10a does not have the bent portion 16, and therefore the manufacturing cost of the integrated coil member 10 can be reduced. Since the integrated coil member 10 is made inexpensive, the cost of the power conversion device 100 can be reduced.

Embodiment 3.
A power conversion device 100 according to embodiment 3 will be described. Fig. 11 is a cross-sectional view showing an outline of the power conversion device 100 according to embodiment 3, taken at the same position as in Fig. 8. In the power conversion device 100 according to embodiment 3, the configuration of the integrated coil member 10 is different from that of embodiment 1.

The integrated portion 10a is a connecting portion 11 that connects the separate transformer coil and reactor coil. In this embodiment, the separate transformer coil is the transformer secondary coil portion 12, and the separate reactor coil is the reactor coil portion 13. In the first embodiment, the integrated coil member 10 is made of a single sheet metal, but in this embodiment, the integrated coil member 10 is formed by connecting the separate transformer coil and reactor coil. The connection between the separate transformer coil and reactor coil at the connecting portion 11 is, for example, welding. With this configuration, the number of coil parts per unit area can be increased when manufacturing the coil parts used in the integrated coil member 10. Since the number of coil parts is increased, the manufacturing cost of the integrated coil member 10 can be reduced. Since the integrated coil member 10 is made at a low cost, the cost of the power conversion device 100 can be reduced.

The transformer secondary coil section 12 and the reactor coil section 13 may also be constructed from metal sheets of different thicknesses and welded at the connecting section 11. With this configuration, the reactor coil section 13 can be increased in coil thickness and reduced in coil width compared to the transformer secondary coil section 12, which faces the transformer primary coil 1 and requires a coil width. Since the coil width of the reactor coil section 13 is reduced, the reactor coil section 13 can be made smaller. Since the reactor coil section 13 is made smaller, the power conversion device 100 can be made smaller and less expensive.

In this embodiment, the connecting portion 11 is thermally connected to the coil mounting surface 53, which is a cooling surface, via the second heat dissipation member 33, which is a heat dissipation member. By configuring it in this manner, the heat generated in the integrated coil member 10 can be efficiently dissipated to the coil mounting surface 53.

Embodiment 4.
A power conversion device 100 according to embodiment 4 will be described. Fig. 12 is a plan view showing an outline of the power conversion device 100 according to embodiment 4. The power conversion device 100 according to embodiment 4 is configured to include a diode module 60 and a semiconductor module 61 in addition to the configuration shown in Fig. 1 of embodiment 1.

The power conversion device 100 includes a rectifier diode 60a arranged next to the transformer 70. In this embodiment, a diode module 60 housing the rectifier diode 60a is arranged next to the transformer 70. The high-voltage coil has a high-voltage transformer terminal connected to the outside, and the low-voltage coil has a low-voltage transformer terminal connected to the outside. The low-voltage transformer terminal is an end opposite to the center tap of the low-voltage coil, and the low-voltage transformer terminal is provided on the side of the transformer 70 where the rectifier diode 60a is arranged, and is electrically connected to the rectifier diode 60a. In this embodiment, the high-voltage coil is the transformer primary coil 1, the low-voltage coil is the transformer secondary coil 2, the high-voltage transformer terminal is the transformer primary terminal 7, and the low-voltage transformer terminal is the transformer secondary terminal 8. The rectifier diode 60a has a diode terminal 60b exposed to the outside from the diode module 60, and the diode terminal 60b and the transformer secondary terminal 8 are connected by, for example, welding.

By configuring in this way, the transformer secondary coil 2 and the rectifier diode 60a can be connected without going through other components such as a control board, thereby reducing the number of parts connecting the transformer secondary coil 2 and the rectifier diode 60a. Since the number of parts is reduced, the cost of the power conversion device 100 equipped with the rectifier diode 60a can be reduced. Note that, although the diode terminal 60b of the rectifier diode 60a and the transformer secondary terminal 8 are connected by welding or the like, this is not limited to this configuration, and the two may be connected using fastening parts such as screws and nuts.

The power conversion device 100 includes a semiconductor switching element 61a arranged next to the transformer 70. In this embodiment, a semiconductor module 61 housing the semiconductor switching element 61a is arranged next to the transformer 70. The transformer coil 71 has a high-voltage side coil and a low-voltage side coil, and a larger current flows through the low-voltage side coil than through the high-voltage side coil. The high-voltage side coil has a high-voltage side transformer terminal connected to the outside, and the low-voltage side coil has a low-voltage side transformer terminal connected to the outside. The high-voltage side transformer terminal is provided on the side where the semiconductor switching element 61a of the transformer 70 is arranged, closer to the reactor 80 than the low-voltage side transformer terminal, and the high-voltage side transformer terminal is electrically connected to the semiconductor switching element 61a. As described above, the high-voltage side transformer terminal is the transformer primary side terminal 7, and the low-voltage side transformer terminal is the transformer secondary side terminal 8. The semiconductor switching element 61a has a semiconductor element terminal 61b exposed to the outside from the semiconductor module 61, and the semiconductor element terminal 61b and the transformer primary side terminal 7 are connected, for example, by welding.

By configuring in this way, the transformer primary coil 1 and the semiconductor switching element 61a can be connected without going through other components such as a control board, thereby reducing the number of components connecting the transformer primary coil 1 and the semiconductor switching element 61a. Since the number of components is reduced, the cost of the power conversion device 100 equipped with the semiconductor switching element 61a can be reduced.

In addition, by arranging the transformer primary terminal 7 between the transformer secondary terminal 8 and the reactor terminal 9, the semiconductor module 61 and the diode module 60 can be arranged on the same side relative to the transformer 70 and the reactor 80. Since the semiconductor module 61 and the diode module 60 can be efficiently arranged on the same side relative to the transformer 70 and the reactor 80, the maximum outer shape of the power conversion device 100 becomes small, and the power conversion device 100 can be made smaller.

Embodiment 5.
A power conversion device 100 according to embodiment 5 will be described. Fig. 13 is a plan view showing an outline of a main part of the power conversion device 100 according to embodiment 5, and shows a transformer core 20, a reactor core 21, and an integrated coil member 10. The power conversion device 100 according to embodiment 5 has a configuration in which two cores are integrated.

The transformer core 20 and the reactor core 21 have an integrated portion, and the transformer core 20 and the reactor core 21 share at least a part of the magnetic path. The integrated portion of the transformer core 20 and the reactor core 21 is the core integration portion 22. In the first embodiment, the transformer core 20 and the reactor core 21 are configured as separate members, but in the present embodiment, the transformer core 20 and the reactor core 21 are integrated into a single member. Therefore, in the core integration portion 22, the magnetic path of the transformer coil 71 and the magnetic path of the reactor coil 3 are shared.

By adopting such a configuration, it is possible to reduce the gap between the transformer core 20 and the reactor core 21 arranged adjacently. Since the gap between the transformer core 20 and the reactor core 21 is reduced, the power conversion device 100 can be made smaller. In addition, since the magnetic path of the transformer coil 71 and the magnetic path of the reactor coil 3 are shared in the core integration section 22, if the transformer core 20 has a cross-sectional area equal to or greater than the core cross-sectional area required for the magnetic circuit to thermally establish the transformer 70, the total core cross-sectional area required for the transformer core 20 and the reactor core 21 can be reduced by sharing the cross-sectional area with the reactor core 21 that has margin for thermal establishment.

Although the present application describes various exemplary embodiments and examples, the various features, aspects, and functions described in one or more embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations.
Therefore, countless modifications not illustrated are conceivable within the scope of the technology disclosed in the present specification, including, for example, modifying, adding, or omitting at least one component, and further, extracting at least one component and combining it with a component of another embodiment.

Various aspects of this disclosure are summarized below as appendices.

(Appendix 1)
a transformer having a transformer core forming a magnetic circuit and a plurality of transformer coils each having a transformer winding portion wound around the transformer core;
A reactor including a reactor core forming a magnetic circuit and a single or multiple reactor coils each having a reactor winding portion wound around the reactor core,
Each of the transformer winding portion and the reactor winding portion is formed into a curved plate shape on a plane,
A power conversion device in which one of the transformer coils and one of the reactor coils are arranged side by side and are electrically and mechanically coupled to each other by an integration portion to form an integrated coil member.
(Appendix 2)
2. The power conversion device according to claim 1, wherein the thickness of the integrated coil member is the same on both the transformer coil side and the reactor coil side.
(Appendix 3)
3. The power conversion device according to claim 1, wherein the integrated coil member is made of a single metal plate.
(Appendix 4)
4. The power conversion device according to claim 1, wherein in the integrated coil member, a width of the plate-shaped conductor of the transformer winding portion is different from a width of the plate-shaped conductor of the reactor winding portion.
(Appendix 5)
a housing having a cooling surface for cooling the transformer and the reactor,
The integral coil member is made of a flat plate,
5. The power conversion device according to claim 1, wherein the integrated coil member is thermally connected to the cooling surface.
(Appendix 6)
a housing having a cooling surface for cooling the transformer and the reactor,
6. The power conversion device according to claim 1, wherein a bottom surface of the transformer core and a bottom surface of the reactor core are thermally connected to the cooling surface which is a single plane.
(Appendix 7)
a housing having a cooling surface for cooling the transformer and the reactor,
the integrated coil member is made of a single sheet metal having a bent portion at the integrated portion,
the transformer winding portion and the reactor winding portion of the integrated coil member are disposed parallel to the cooling surface, and the transformer winding portion of the integrated coil member is disposed farther away from the cooling surface than the reactor winding portion of the integrated coil member,
7. The power conversion device according to claim 1, wherein another transformer winding portion is disposed between the transformer winding portion of the integrated coil member and the cooling surface.
(Appendix 8)
8. The power conversion device according to claim 7, wherein the reactor winding portion and the separate transformer winding portion of the integrated coil member are thermally connected to the cooling surface via a heat dissipation member.
(Appendix 9)
The transformer coil has a high-voltage side coil and a low-voltage side coil,
A larger current flows through the low-voltage coil than through the high-voltage coil,
The power conversion device according to any one of claims 1 to 8, wherein the transformer coil portion of the integrated coil member is the low-voltage side coil.
(Appendix 10)
The transformer coil has a plurality of high-voltage side coils and a plurality of low-voltage side coils,
A larger current flows through the low-voltage coil than through the high-voltage coil,
10. The power conversion device according to claim 1, wherein the low-voltage side coil and the high-voltage side coil are alternately arranged along an extension direction of a portion of the transformer core around which the transformer winding portion is wound.
(Appendix 11)
a housing having a cooling surface for cooling the transformer and the reactor,
the transformer coil portion of the integrated coil member is the low-voltage side coil,
11. The power conversion device according to claim 10, wherein another low-voltage side coil is disposed between the low-voltage side coil of the integrated coil member and the cooling surface.
(Appendix 12)
The transformer coil has a high-voltage side coil and a low-voltage side coil,
A larger current flows through the low-voltage coil than through the high-voltage coil,
the transformer coil portion of the integrated coil member is the low-voltage side coil,
the low-voltage side coil is a center-tapped coil having a center tap portion,
12. The power conversion device according to any one of claims 1 to 11, wherein the integrated portion is coupled to the center tap portion.
(Appendix 13)
13. The power conversion device according to claim 1, wherein the transformer coil and the reactor coil are integrated by a resin member, and a resin case is formed to accommodate the transformer coil and the reactor coil.
(Appendix 14)
a housing having a cooling surface for cooling the transformer and the reactor,
14. The power conversion device according to claim 13, wherein the resin case is fixed to the housing at a portion between the transformer coil and the reactor coil.
(Appendix 15)
The power conversion device according to any one of claims 1 to 14, wherein the integration portion is a connection portion that connects the transformer coil and the reactor coil, which are separate from each other.
(Appendix 16)
a housing having a cooling surface for cooling the transformer and the reactor,
16. The power conversion device according to claim 15, wherein the connecting portion is thermally connected to the cooling surface via a heat dissipation member.
(Appendix 17)
a housing having a cooling surface for cooling the transformer and the reactor,
17. The power conversion device according to any one of claims 1 to 16, wherein one or both of the transformer coil portion of the integrated coil member and the reactor coil portion of the integrated coil member are thermally connected to the cooling surface via a heat dissipation member.
(Appendix 18)
a first extending direction in which a portion of the transformer core around which the transformer winding portion is wound extends and a second extending direction in which a portion of the reactor core around which the reactor winding portion is wound extends are parallel to each other;
18. The power conversion device according to any one of claims 1 to 17, wherein the transformer and the reactor are disposed adjacent to each other in a direction perpendicular to the first extension direction and the second extension direction.
(Appendix 19)
The transformer coil has a transformer terminal connected to an external device,
The reactor coil has a reactor terminal connected to an external device,
19. The power conversion device according to claim 18, wherein the transformer terminal and the reactor terminal are arranged on the same side with respect to the adjacent transformer and reactor when viewed in the first extension direction.
(Appendix 20)
Rectifier diodes are arranged in line with the transformer,
the high-voltage side coil has a high-voltage side transformer terminal connected to an external device,
the low-voltage side coil has a low-voltage side transformer terminal connected to an external device,
the low-voltage side transformer terminal is an end of the low-voltage side coil opposite to the center tap portion,
13. The power conversion device according to claim 12, wherein the low-voltage side transformer terminal is provided on a side of the transformer where the rectifier diode is arranged and is electrically connected to the rectifier diode.
(Appendix 21)
A semiconductor switching element is arranged next to the transformer,
The transformer coil has a high-voltage side coil and a low-voltage side coil,
A larger current flows through the low-voltage coil than through the high-voltage coil,
the high-voltage side coil has a high-voltage side transformer terminal connected to an external device,
the low-voltage side coil has a low-voltage side transformer terminal connected to an external device,
the high-voltage side transformer terminal is provided on a side of the transformer on which the semiconductor switching element is arranged, and closer to the reactor than the low-voltage side transformer terminal;
20. The power conversion device according to claim 19, wherein the high-voltage side transformer terminal is electrically connected to the semiconductor switching element.
(Appendix 22)
The transformer core and the reactor core have an integrated portion,
22. The power conversion device according to any one of claims 1 to 21, wherein the transformer core and the reactor core share at least a portion of a magnetic path.

1, 1a Transformer primary coil, 2, 2a Transformer secondary coil, 3, 3a Reactor coil, 4 Transformer winding portion, 5 Reactor winding portion, 6 Center tap portion, 7 Transformer primary terminal, 8 Transformer secondary terminal, 9 Reactor terminal, 10 Integrated coil member, 10a Integration portion, 11 Connection portion, 12 Transformer secondary coil portion, 13 Reactor coil portion, 13a Connection portion, 14 Transformer primary interlayer connection portion, 15 Reactor interlayer connection portion, 16 Bending portion, 20 Transformer core, 20a Center core, 21 Reactor core, 21a Center core, 22 Core integration portion, 30 Spring, 31 Fixing member, 32 First heat dissipation member, 33 Second heat dissipation member, 40 Resin case, 41 Positioning wall, 42 Positioning protrusion, 43 Fixing portion, 50 Housing, 51 Cooling surface, 52 Core mounting surface, 53 Coil mounting surface, 54 Positioning hole, 60 Diode module, 60a Rectifier diode, 60b Diode terminal, 61 Semiconductor module, 61a Semiconductor switching element, 61b Semiconductor element terminal, 70 Transformer, 71 Transformer coil, 80 Reactor, 90 Smoothing capacitor, 95 DC power source, 100 Power conversion device

Claims (22)

a transformer having a transformer core forming a magnetic circuit and a plurality of transformer coils each having a transformer winding portion wound around the transformer core;
A reactor including a reactor core forming a magnetic circuit and a single or multiple reactor coils each having a reactor winding portion wound around the reactor core,
Each of the transformer winding portion and the reactor winding portion is formed into a curved plate shape on a plane,
A power conversion device in which one of the transformer coils and one of the reactor coils are arranged side by side and are electrically and mechanically coupled to each other by an integration portion to form an integrated coil member. The power conversion device according to claim 1, wherein the thickness of the integrated coil member is the same on both the transformer coil side and the reactor coil side. The power conversion device according to claim 1, wherein the integrated coil member is made of a single metal plate. The power conversion device according to claim 1, wherein the width of the plate-shaped conductor of the transformer winding section and the width of the plate-shaped conductor of the reactor winding section in the integrated coil member are different. a housing having a cooling surface for cooling the transformer and the reactor,
The integral coil member is made of a flat plate,
The power converter of claim 1 , wherein the integral coil member is thermally connected to the cooling surface. a housing having a cooling surface for cooling the transformer and the reactor,
The power conversion device according to claim 1 , wherein a bottom surface of the transformer core and a bottom surface of the reactor core are thermally connected to the cooling surface which is formed of the same plane. a housing having a cooling surface for cooling the transformer and the reactor,
the integrated coil member is made of a single sheet metal having a bent portion at the integrated portion,
the transformer winding portion and the reactor winding portion of the integrated coil member are disposed parallel to the cooling surface, and the transformer winding portion of the integrated coil member is disposed farther away from the cooling surface than the reactor winding portion of the integrated coil member,
The power conversion device according to claim 1 , wherein another transformer winding portion is disposed between the transformer winding portion of the integrated coil member and the cooling surface. The power conversion device according to claim 7, wherein the reactor winding portion and the separate transformer winding portion of the integrated coil member are thermally connected to the cooling surface via a heat dissipation member. The transformer coil has a high-voltage side coil and a low-voltage side coil,
A larger current flows through the low-voltage coil than through the high-voltage coil,
8. The power conversion device according to claim 1, wherein the transformer coil portion of the integrated coil member is the low-voltage side coil. The transformer coil has a plurality of high-voltage side coils and a plurality of low-voltage side coils,
A larger current flows through the low-voltage coil than through the high-voltage coil,
2. The power conversion device according to claim 1, wherein the low-voltage side coil and the high-voltage side coil are alternately arranged along an extension direction of the portion of the transformer core around which the transformer winding portion is wound. a housing having a cooling surface for cooling the transformer and the reactor,
the transformer coil portion of the integrated coil member is the low-voltage side coil,
The power conversion device according to claim 10 , wherein another coil on the low voltage side is disposed between the coil on the low voltage side of the integrated coil member and the cooling surface. The transformer coil has a high-voltage side coil and a low-voltage side coil,
A larger current flows through the low-voltage coil than through the high-voltage coil,
the transformer coil portion of the integrated coil member is the low-voltage side coil,
the low-voltage side coil is a center-tapped coil having a center tap portion,
The power conversion device according to claim 1 , wherein the integrated portion is coupled to the center tap portion. The power conversion device according to claim 1, wherein the transformer coil and the reactor coil are integrated with a resin member, and a resin case is formed to house the transformer coil and the reactor coil. a housing having a cooling surface for cooling the transformer and the reactor,
The power conversion device according to claim 13 , wherein the resin case is fixed to the housing at a portion between the transformer coil and the reactor coil. The power conversion device according to claim 1, wherein the integration section is a connection section that connects the transformer coil and the reactor coil, which are separate bodies. a housing having a cooling surface for cooling the transformer and the reactor,
The power conversion device according to claim 15 , wherein the coupling portion is thermally connected to the cooling surface via a heat dissipation member. a housing having a cooling surface for cooling the transformer and the reactor,
The power conversion device according to claim 1 , wherein one or both of the transformer coil portion of the integrated coil member and the reactor coil portion of the integrated coil member are thermally connected to the cooling surface via a heat dissipation member. a first extending direction in which a portion of the transformer core around which the transformer winding portion is wound extends and a second extending direction in which a portion of the reactor core around which the reactor winding portion is wound extends are parallel to each other;
The power conversion device according to claim 1 , wherein the transformer and the reactor are disposed adjacent to each other in a direction perpendicular to the first extension direction and the second extension direction. The transformer coil has a transformer terminal connected to an external device,
The reactor coil has a reactor terminal connected to an external device,
The power conversion device according to claim 18 , wherein the transformer terminal and the reactor terminal are arranged on the same side with respect to the adjacent transformer and reactor when viewed in the first extension direction. Rectifier diodes are arranged in line with the transformer,
the high-voltage side coil has a high-voltage side transformer terminal connected to an external device,
the low-voltage side coil has a low-voltage side transformer terminal connected to an external device,
the low-voltage side transformer terminal is an end of the low-voltage side coil opposite to the center tap portion,
The power conversion device according to claim 12 , wherein the low-voltage side transformer terminal is provided on a side of the transformer where the rectifier diode is arranged, and is electrically connected to the rectifier diode. A semiconductor switching element is arranged next to the transformer,
The transformer coil has a high-voltage side coil and a low-voltage side coil,
A larger current flows through the low-voltage coil than through the high-voltage coil,
the high-voltage side coil has a high-voltage side transformer terminal connected to an external device,
the low-voltage side coil has a low-voltage side transformer terminal connected to an external device,
the high-voltage side transformer terminal is provided on a side of the transformer on which the semiconductor switching element is arranged, and closer to the reactor than the low-voltage side transformer terminal;
The power conversion device according to claim 19 , wherein the high-voltage side transformer terminal is electrically connected to the semiconductor switching element. The transformer core and the reactor core have an integrated portion,
The power conversion device according to claim 1 , wherein the transformer core and the reactor core share at least a part of a magnetic path.

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