WO2023209880A1

WO2023209880A1 - Power conversion device

Info

Publication number: WO2023209880A1
Application number: PCT/JP2022/019118
Authority: WO
Inventors: 健篠▲崎▼; 裕輔木本; 翔太佐藤; 寛之矢原; 雄二白形
Original assignee: 三菱電機株式会社
Priority date: 2022-04-27
Filing date: 2022-04-27
Publication date: 2023-11-02
Also published as: JPWO2023209880A1; JP7202053B1

Abstract

A power conversion device (100) comprises: an outer box for accommodating an electric component; a cooler (31) which has a plurality of pin-shaped fins (311) and a base plate (312) as a lid of the outer box, and in which the plurality of fins (311) are open to the surrounding space; and a blower (32) that has rotary blades (323), that is installed at the center of the plurality of fins (311), and that blows air to the plurality of fins (311), of the cooler (31), arranged around the blower. The plurality of fins (311) are radially disposed along a direction (F) of a straight line connecting a blade root portion (323a) and a blade tip portion (323b) of each of the rotary blades (323) of the blower (32).

Description

power converter

The present disclosure relates to a power conversion device having a heat dissipation structure.

In power conversion devices such as inverter devices, converter devices, or charging devices, air-cooled heat dissipation structures that do not use cooling water equipment are known in order to reduce size and weight.

In Patent Document 1, the first casing and the second casing are arranged vertically so that the bottom surface of the first metal substrate and the bottom surface of the second metal substrate, on which electrical components are mounted, face each other. The first metal substrate and the second metal substrate are arranged adjacent to each other, and are thermally coupled via the first radiation fin and the second radiation fin. The first plate-shaped heat radiating fin and the second plate-shaped heat radiating fin are connected at their tips to form a flow path for air refrigerant passed by the fan.

JP 2019-22293 Publication

In Patent Document 1, in order to increase the heat dissipation area, fins are placed opposite each other to form a flow path through which air refrigerant flows, and because the fins are not open to the surrounding space, the fan may stop or the running air may pass through. If it is not flushed, cooling performance will be drastically reduced. In addition, if the heat generation of electrical components increases, it is necessary to increase the size of the fins, increase the number of blowers, or increase the air volume of the fan. may lead to

The present disclosure has been made in view of the above, and aims to provide a power conversion device that can be made smaller and lighter while still having efficient and high heat dissipation ability.

In order to solve the above-mentioned problems and achieve the purpose, a power conversion device according to the present disclosure includes an outer box that stores electrical components, a base plate that is a lid of the outer box, and a pin-shaped pin that stands up on the base plate. A cooler having a plurality of fins, the plurality of fins being open to the surrounding space, and a rotor blade installed in the center of the plurality of fins and blowing air to the plurality of fins of the cooler arranged around the fins. A blower having a. The plurality of fins are arranged radially along a first direction that is a straight line connecting a blade root and a blade tip of a rotary blade of the blower.

According to the power conversion device of the present disclosure, it is possible to reduce the size and weight while maintaining efficient and high heat dissipation ability.

A perspective view showing the configuration of a power conversion device according to Embodiment 1 A cross-sectional view showing the configuration of a power conversion device according to Embodiment 1 A cross-sectional view for explaining the positional relationship between a blower and fins in the power conversion device according to Embodiment 1. A top view showing the configuration of a power conversion device according to Embodiment 1 A side view showing the configuration of a power conversion device according to Embodiment 1 Top view showing the configuration of a power conversion device according to Embodiment 2 A cross-sectional view showing the configuration of a power conversion device according to Embodiment 2 Cross-sectional view showing the configuration of a power conversion device according to Embodiment 3 Cross-sectional view showing the configuration of a power conversion device according to Embodiment 4

Below, a power conversion device according to an embodiment will be described in detail based on the drawings.

Embodiment 1.
FIG. 1 is a perspective view showing the configuration of a power conversion device according to Embodiment 1. FIG. 2 is a sectional view showing the configuration of the power conversion device according to the first embodiment. FIG. 2 is a cross-sectional view taken along line II-II in FIG. FIG. 3 is a cross-sectional view for explaining the positional relationship between the blower and the fins in the power conversion device according to the first embodiment. FIG. 4 is a top view showing the configuration of the power conversion device according to the first embodiment. FIG. 5 is a side view showing the configuration of the power conversion device according to the first embodiment.

The power conversion device 100 is a power conversion device installed in, for example, an electric aircraft, an electric vehicle, a hybrid vehicle, a fuel cell vehicle, or the like. As shown in FIGS. 1 to 3, the power conversion device 100 mainly includes an outer box 2, a cooling device 3, and a plurality of electrical components 4 that generate heat.

The outer box 2 is a casing provided to cover the electrical components 4. The outer box 2 has an equipment area for storing and protecting electrical components 4 therein. The cooler 31 also serves as a lid that partitions the equipment area from the outside air. The outer box 2 and the cooler 31 form a sealed structure. The outer box 2 is formed of a thin plate of metal such as aluminum, aluminum alloy, or stainless steel. In order to prevent water and dust from entering the outer box 2, the outer box 2 and the cooler 31 are joined together using means such as an O-ring, a gasket, or friction stir welding. As shown in FIG. 5, the outside of the outer box 2 does not necessarily need to have a smooth surface, and may be provided with a heat dissipation structure 21 such as an uneven structure as long as the inside can be sealed. Furthermore, a connector or the like for transmitting the converted power may be installed in the outer box 2 as long as water and dust are prevented from entering.

The cooling device 3 includes a cooler 31 and a blower 32. The cooler 31 also serves as a lid for the outer box 2. The blower 32 blows air through the cooler 31. The cooler 31 is made of a material with good thermal conductivity, such as aluminum, aluminum alloy, copper, or iron. The cooler 31 includes a base plate 312 as a lid of the outer box 2 and a plurality of fins 311 erected on the base plate 312. The top and side surfaces of the plurality of fins 311 are open to the surrounding space. A plurality of electrical components 4 are installed on the surface of the base plate 312 opposite to the surface on which the fins 311 are arranged. When the plurality of electrical components 4 are energized, a part of the electrical power is converted into heat as power loss, and the plurality of electrical components 4 generate heat and the temperature rises. This heat generation is conducted to the fins 311 via the base plate 312. The heat conducted to the fins 311 is radiated to the surroundings through the air. The blower 32 is a centrifugal blower that takes in air from an axial center portion 321 and discharges air from a side portion 322, which is an outlet of the blower 32, and is located perpendicular to the axis, as shown by arrow E. . Air discharged from the side part 322 passes between the plurality of fins 311 of the cooler 31.

The fins 311 are pin-shaped radially erected along the straight line F (direction of the broken arrow in FIG. 4) connecting the blade root 323a and the blade tip 323b of the rotary blade 323 of the blower 32. It's a fin. The direction F of the dashed arrow corresponds to the first direction. The fins 311 are integrally molded with the base plate 312 by, for example, aluminum die casting or a metal three-dimensional printer. Further, the fins 311 may be separately produced and bonded to the base plate 312 with an adhesive having good thermal conductivity, or may be mechanically bonded by caulking or the like. Further, the fins 311 may have a circular cross section, but are preferably pin-shaped fins with an elliptical cross section whose long sides are in the direction of air flow so as to follow the flow of air discharged from the blower 32. Further, the fins 311 are erected such that the distance between the fins 311 in the circumferential direction and the radial direction (direction F) increases as the distance from the blower 32 increases.

The blower 32 is fixed to the base plate 312 using adhesive, screws, or other means. Electric power is supplied to the blower 32 from the outside through a lead wire (not shown) or the like. The fins 311 are not erected in the area where the blower 32 is fixed and the area 5 around the blower. The blower peripheral area 5 is an area between the blower 32 and the fins 311. The blower surrounding area 5 is an annular area within a certain distance from the blower 32. The blower peripheral area 5 corresponds to the first spatial area. As described above, the blower 32 takes in air from the axial center portion 321 and discharges air from the side portion 322, which is the outlet of the blower 32 and is located perpendicular to the axis. The air discharged from the side part 322 passes between the fins 311 installed on the cooler 31. In order for the air discharged from the side surface portion 322 to sufficiently pass between the fins 311, the blower 32 is configured to move the side surface portion 322 of the blower 32 in the vertical direction (extending direction of the fins 311), as shown in FIG. The center position C is fixed to be lower than the position K of the upper end surface of the fin 311 in the upright direction. A mounting stand or the like may be provided between the base plate 312 and the blower 32 in order to fix the blower 32 to the base plate 312 so as to satisfy this fixing condition.

Next, the operation of power conversion device 100 in Embodiment 1 will be described. For example, in order to step up or step down the voltage or drive a motor (not shown), etc., the electrical components 4 such as semiconductor elements, transformers, and reactors installed on the base plate 312 and the inside of the bottom surface of the outer box 2 are installed. The electrical components 4 such as the control board that have been installed operate. These electrical components 4 generate heat depending on their operating conditions. Electrical components 4 installed on the base plate 312 are conducted to the fins 311 via the base plate 312. The heat conducted to the fins 311 is radiated to the surroundings by exchanging heat with the air discharged from the blower 32, so that the electrical component 4 is cooled. Electrical components 4 installed inside the outer box 2 conduct heat to the wall surface of the outer box 2. The heat conducted to the wall surface of the outer box 2 is radiated to the surroundings by exchanging heat with the air outside the outer box 2, so that the electrical components 4 are cooled.

As described above, the power converter 100 according to the first embodiment includes the outer box 2 that stores the electrical components 4, the base plate 312 that is the lid of the outer box 2, and the plurality of fins 311 that are vertically provided on the base plate 312. and a blower 32 having rotary blades that is installed in the center of the plurality of fins 311 and blows air to the plurality of fins 311 arranged around the fins 311. By covering the box 2, water and dust are prevented from entering into the outer box 2 from the outside. Furthermore, since the fins 311 are open to the surrounding space, even if the blower 32 should stop, the electric components 4 can be efficiently cooled by natural convection.

Further, the plurality of fins 311 are arranged radially along the direction F of a straight line connecting the blade root portion 323a and the blade tip portion 323b of the rotor blade of the blower 32. Further, a blower peripheral area 5 is provided between the blower 32 and the fins 311, which is a space where the fins 311 are not provided. Further, the cross-sectional shape of the fin 311 is an ellipse whose long side is in the direction F. According to such a configuration, the air discharged from the side surface portion 322, which is the outlet of the blower 32, flows along the fins 311, so that pressure loss is reduced and the air flow rate can be increased. Therefore, it becomes possible to efficiently radiate heat from the fins 311. Therefore, even if the amount of heat generated by the power converter 100 increases due to the increase in the output of the power converter 100, the power converter 100 can be effectively operated while suppressing the increase in the size of the power converter 100 or the blower 32. Can be cooled.

In addition, by installing the power conversion device 100 in a desired system so that the cooling device 3 is installed on the upper side in the direction of gravity, the air whose temperature has increased inside the housing made up of the outer box 2 flows upward in the direction of gravity. Therefore, it can be effectively cooled by the cooler 31. Furthermore, in the event that the blower 32 stops, the cooling effect due to natural convection can be increased.

Embodiment 2.
FIG. 6 is a top view showing the configuration of the power conversion device according to the second embodiment. FIG. 7 is a sectional view showing the configuration of a power conversion device according to the second embodiment. In Embodiment 2, the same components as in Embodiment 1 are given the same reference numerals, and redundant explanations will be omitted.

As shown in FIGS. 6 and 7, in the power conversion device 101 of the second embodiment, a shielding plate 6 that covers the area 5 around the blower is provided. The shielding plate 6 prevents the air discharged from the side surface portion 322, which is the outlet of the blower 32, from circulating again to the axial center portion 321 of the blower 32 without passing through the fins 311. The shielding plate 6 is manufactured separately and is mechanically fixed to the blower 32 and the fins 311. Further, if it is possible to mold the shielding plate 6 without interfering with the attachment of the blower 32, the shielding plate 6 may be molded integrally with the cooler 31 using aluminum die casting, a metal three-dimensional printer, or the like.

According to the second embodiment, the shielding plate 6 is installed in the area 5 around the blower where the fins 311 are not provided, so that the air discharged from the side surface 322, which is the outlet of the blower 32, is By circulating the air again to the axial center portion 321 of the blower 32 without passing through the fins 311, it is possible to prevent the air flow rate passing through the fins 311 from decreasing. Moreover, it is also possible to prevent the temperature of the blower 32 from increasing due to the air temperature rising during the circulation process, and shortening the life of the blower 32.

Embodiment 3.
FIG. 8 is a cross-sectional view showing the configuration of a power conversion device according to Embodiment 3. In Embodiment 3, the same components as in Embodiment 1 are given the same reference numerals, and redundant explanation will be omitted.

As shown in FIG. 8, in the power conversion device 102 according to the third embodiment, there is a gap between the base plate 312 and the electric component 4 installed in the blower peripheral area 5 on the back surface of the base plate 312. A heat diffusion member 7 that diffuses heat in the surface direction D is installed.

Unlike heat transfer grease or heat transfer sheets, the heat diffusion member 7 contains a carbon compound that has excellent heat transfer ability in the planar direction, and utilizes the latent heat accompanying the evaporation and condensation of the working fluid sealed inside. etc. It is desirable that the heat diffusion member 7 is installed up to a region opposite to the region where the fins 311 are erected. Further, a heat pipe, which is a heat dissipation component that utilizes latent heat, may be used as the heat diffusion member 7 and integrally molded inside the base plate 312.

According to the third embodiment, since the heat diffusion member 7 is installed, the heat of the blower 32 and the electric components 4 installed in the area 5 around the blower can be effectively transported to the fins 311. . Therefore, the electrical components 4 can be efficiently cooled, and the heat generated by the blower 32 can also be cooled by the fins 311. Furthermore, in order to suppress the temperature rise of the electrical components 4, it is not necessary to increase the size of the fins 311 in the vertical direction, increase the number of fins 311, or increase the size of the blower 32, so that the power converter 102 does not need to be enlarged. It is possible to prevent the increase in size. Furthermore, if the temperature distribution of the base plate 312 can be made uniform by the heat diffusion member 7, the cooler 31 can be made smaller and lighter by reducing the number of fins 311 and making the blower 32 smaller. be able to.

Embodiment 4.
FIG. 9 is a sectional view showing the configuration of a power conversion device according to Embodiment 4. In Embodiment 4, the same components as in Embodiment 1 are given the same reference numerals, and redundant explanation will be omitted.

As shown in FIG. 9, in the power conversion device 103 according to the fourth embodiment, the upper surface 312a of the base plate 312 has an inclined surface that decreases as the distance from the central position where the blower 32 is installed to the periphery increases. That is, the base plate 312 is thicker at the position where the blower 32 is installed, and the upper surface 312a of the base plate 312 is sloped so that the thickness decreases in the direction in which the fins 311 are installed. are doing.

Since the upper surface 312a of the base plate 312 has an inclination, the apex heights of the fins 311 in the upright direction are equal, but the fin lengths are not uniform. Further, the slope of the base plate 312 may not be a straight line, but may be an arc shape.

As described above, according to the fourth embodiment, the upper surface 312a of the base plate 312 has an inclined surface that decreases as the distance from the central position where the blower 32 is installed to the periphery increases. It is possible to suppress the included dust from staying on the base plate 312. Therefore, it is possible to prevent a decrease in cooling performance due to the accumulation of dust.

In addition, by applying a water-repellent coating to the fins 311 and the base plate 312, it is possible to prevent water from staying on the base plate 312. Therefore, the base plate 312 deteriorates due to corrosion and holes open, resulting in a sealed state. This can prevent the situation from becoming impossible to secure.

The configurations shown in the embodiments described above are examples of the contents of the present disclosure, and can be combined with other known technologies, and the configurations can be modified without departing from the gist of the present disclosure. It is also possible to omit or change parts.

2 Outer box, 3 Cooling device, 4 Electrical components, 5 Blower peripheral area, 6 Shielding plate, 7 Heat diffusion member, 21 Heat dissipation structure, 31 Cooler, 32 Blower, 100, 101, 102, 103 Power conversion device, 311 Fin , 312 base plate, 312a upper surface, 321 axial center, 322 side surface, 323 rotor, 323a blade root, 323b blade tip.

Claims

An outer box that stores electrical components;
A cooler having a base plate that is a lid of the outer box, and a plurality of pin-shaped fins erected on the base plate, the plurality of fins being open to the surrounding space;
a blower having rotary blades that is installed in the center of the plurality of fins and blows air to the plurality of fins of the cooler arranged around the fins;
Equipped with
A power conversion device characterized in that the plurality of fins are arranged radially along a first direction that is a direction of a straight line connecting a blade root and a blade tip of the rotary blade of the blower. .
The power conversion device according to claim 1, wherein a cross section of each of the plurality of fins is an ellipse with a long side in the first direction.
The power conversion device according to claim 1 or 2, wherein a first spatial region in which the fins are not arranged exists between the blower and the plurality of fins.
The power conversion device according to claim 3, further comprising a shielding plate that covers the first spatial region.
Any one of claims 1 to 4, further comprising a heat diffusion member that diffuses heat in a surface direction of the base plate between the base plate and the electric component arranged on the back surface of the base plate. The power conversion device according to one of the above.
The power conversion device according to any one of claims 1 to 5, characterized in that an outer surface of the outer box is provided with unevenness extending in the direction in which the fins extend.
The power conversion device according to any one of claims 1 to 6, wherein a vertical center position of the blower is located at a position lower than an upper end surface of the fin.
The power conversion device according to any one of claims 1 to 7, wherein the fins are arranged upright such that the distance between the fins increases as the distance from the blower increases.
The power conversion device according to any one of claims 1 to 8, wherein the upper surface of the base plate has an inclined surface that decreases as the distance from the center position where the blower is installed increases.