CN205610465U - Power conversion device - Google Patents

Abstract

A power conversion device capable of improving the cooling performance of a capacitor without causing the problems of increasing the number of parts and complicating assembly work. In a power conversion device (1) in which a circuit board (2B) on which a capacitor (4) is mounted is housed inside a housing case (10), the housing case (10) has a main cover portion (12a) and a capacitor housing portion (12b), the main cover part (12a) is arranged opposite to the capacitor mounting surface (2Ba) of the circuit board (2B), and the capacitor housing part (12b) is formed on the main cover part (12a) so as to be in contact with the capacitor ( 4) The corresponding part protrudes outward, so that the capacitor (4) is housed inside, and the main cover part (12a) and the capacitor housing part (12b) are integrally formed.

Description

power conversion device

technical field

The utility model relates to a power conversion device, and in more detail, relates to a cooling structure for a capacitor installed on a circuit substrate.

Background technique

In a power conversion device in which a large-capacity capacitor is mounted on a circuit board, various cooling structures are provided in order to prevent the influence of heat generated from the capacitor. For example, in Patent Document 1, a hole through which a capacitor passes is formed in a housing case covering a circuit board, and the capacitor is arranged outside the housing case. A cover member covering the periphery of the capacitor is attached to the hole of the housing case. The cover member prevents water and dust from entering the interior through holes formed in the housing case. According to this power conversion device, heat from the capacitor can be released to the outside of the storage case through the entire surface of the cover member, and cooling performance can be improved.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2000-173861

In addition, in the cooling structure described above, it is necessary to prepare cover members according to the number of capacitors mounted on the circuit board. Furthermore, it is necessary to interpose a sealing member between the cover member and the housing case. Therefore, not only does the number of parts to be handled increase, but the assembly work of the power conversion device may become complicated.

Utility model content

In view of the above-mentioned circumstances, an object of the present invention is to provide a power conversion device capable of improving the cooling performance of a capacitor without increasing the number of parts and complicating assembly work.

In order to achieve the above object, the power conversion device of the present invention accommodates the circuit board on which the capacitor is mounted inside the storage case, and it is characterized in that the above-mentioned storage case has a main cover part and a capacitor storage part, and the above-mentioned main cover part and the above-mentioned The capacitor mounting surface of the circuit board is arranged facing each other, the capacitor housing part is formed on the main cover part in a form protruding outward at a part corresponding to the capacitor, and the capacitor is accommodated inside, and the main cover part and the capacitor are accommodated. The part is formed as one.

In addition, the present invention is based on the above-mentioned power conversion device, and is characterized in that, on the outside of the above-mentioned housing case, a ventilation passage is formed at a position surrounding the above-mentioned capacitor housing part, and a ventilation passage is arranged from one side of the above-mentioned ventilation passage to the other. A ventilation fan for ventilation on one side.

In addition, the present invention is based on the above-mentioned power conversion device, wherein the capacitor housing part is formed in an elliptical column shape, and a plurality of capacitors are housed inside the capacitor housing part, and a plurality of capacitors are arranged along the ventilation path. The form of the ventilation direction is mounted on the above-mentioned circuit board.

In addition, the present invention is based on the power conversion device described above, wherein a vent hole communicating with the outside of the housing case is formed in the capacitor housing portion, and the vent hole is covered with a moisture-permeable waterproof sheet.

According to the present invention, since the main cover part of the housing case and the capacitor housing part are integrally formed, it has nothing to do with the number of capacitors mounted on the circuit board, and the number of parts will not increase. Furthermore, it is not necessary to provide a sealing member between the main cover portion and the capacitor housing portion. Therefore, it is possible to improve the cooling performance of the capacitor without causing the problems of increasing the number of parts and complicating assembly work.

Description of drawings

FIG. 1 is a perspective view showing the appearance of a power conversion device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of main parts of the power conversion device shown in FIG. 1 .

Fig. 3 is a sectional side view of the power conversion device shown in Fig. 1 .

FIG. 4 is a partial cutaway top view of the power conversion device shown in FIG. 1 .

FIG. 5 is a perspective view of a circuit board used in the power conversion device shown in FIG. 1 .

6 is a perspective view of a second case portion constituting a housing case of the power conversion device shown in FIG. 1 .

Fig. 7 is a perspective view of a frame member constituting a ventilation unit of the power conversion device shown in Fig. 1 .

FIG. 8 is a perspective view of a second case portion applied to a power conversion device according to Modification 1 of the present invention.

9 is a perspective view of a second case portion of a circuit board applied to the power conversion device shown in FIG. 8 .

10 is a cross-sectional view of main parts of a power conversion device according to Modification 2 of the present invention.

FIG. 11 is a perspective view showing a part of main parts of the power conversion device shown in FIG. 10 in cutaway.

(Symbol Description)

2B...circuit board

2Ba...Mounting surface

4…capacitor

10…containment shell

12a...Main cover

12b...Capacitor housing

20…Ventilation Department

21…Ventilation pathway

40…frame members

50…ventilation fan

112b...Capacitor storage unit

212b…Capacitor storage unit

212c...opening

212d…Moisture-permeable waterproof sheet

detailed description

Hereinafter, preferred embodiments of the power conversion device of the present invention will be described in detail with reference to the drawings.

1 to 4 show a power conversion device according to an embodiment of the present invention. The power conversion device 1 exemplified here is used to convert an AC voltage supplied from a commercial power supply into a desired frequency and amplitude and then supply it to a load such as a motor, and includes a housing case 10 for accommodating circuit boards 2A and 2B, and a power converter for converting power. The ventilation unit 20 for cooling the components of the device 1 , that is, the semiconductor modules 3 such as IGBT and the capacitor 4 .

The storage case 10 is configured to include a first case portion 11 and a second case portion 12 . The first case portion 11 constitutes a part of the outline of the power conversion device 1 and is formed in a substantially rectangular flat plate shape from a resin material. Two circuit boards 2A and 2B having different sizes are supported on the inner surface side of the first case portion 11 in a state of being stacked on each other. As shown in FIGS. 2 to 5 , the circuit board with a larger external dimension (hereinafter referred to as the main circuit board 2A) is formed into a rectangle slightly smaller than the first housing part 11, and is aligned with the inner surface of the first housing part 11. relative configuration. The smaller circuit board (hereinafter referred to as sub-circuit board 2B) has approximately 1/2 the width of the first case portion 11 and is arranged in the right half of the first case portion 11 in FIG. 2 . On the sub circuit board 2B, heat-generating components such as the above-mentioned semiconductor module 3 and capacitor 4 are mainly assembled and mounted. Although not clearly shown in the figure, the above-mentioned main circuit board 2A and sub circuit board 2B are electrically connected to each other and constitute a control circuit necessary for power conversion.

As shown in FIG. 5 , the semiconductor module 3 used in this embodiment is formed in a substantially rectangular parallelepiped shape, and has screw fixing portions 3 a on upper and lower side surfaces parallel to each other. The screw fixing portion 3 a is a tongue-shaped portion protruding from an edge portion on the side of the semiconductor module 3 away from the heat dissipation surface 3 b of the sub circuit board 2B. Screw through holes 3c through which mounting screws B are inserted are provided in the respective screw fixing portions 3a. On the main circuit board 2A and the sub circuit board 2B, through holes 2 a are formed at portions facing the screw through holes 3 c of the semiconductor module 3 . The through hole 2a is a circular opening having an inner diameter larger than that of the screw through hole 3c.

Capacitor 4 is formed in a cylindrical shape, and is mounted on sub circuit board 2B in a state where one end surface faces mounting surface 2Ba of sub circuit board 2B. In the present embodiment, capacitors 4 are arranged at the upper end of sub circuit board 2B, at the upper left corner portion and at the obliquely lower right portion of the portion.

As shown in FIGS. 2 to 4 and 6 , the second case portion 12 is a resin molded product having a size to cover the first case portion 11 , and has a main cover portion 12 a and a capacitor housing portion 12 b. Main cover portion 12a is a plate-shaped portion arranged to face mounting surfaces 2Aa, 2Ba of circuit boards 2A, 2B. The capacitor accommodating portion 12b independently accommodates the capacitors 4 mounted on the sub circuit board 2B, and is integrally formed with the main cover portion 12a in a form protruding outward from the main cover portion 12a. In the present embodiment, the capacitor accommodating portion 12 b is configured as a bottomed cylindrical airtight container that is open only at a portion facing the mounting surface 2Ba of the sub circuit board 2B. The size of the capacitor housing portion 12 b is set so that a gap of 0.5 mm is formed between the end surface and the peripheral surface of the capacitor 4 when the capacitor 4 is accommodated therein.

In addition, a communication hole 12 c is provided in a portion of the main cover portion 12 a of the second case portion 12 corresponding to the semiconductor module 3 . The communication hole 12c is a substantially rectangular opening that can pass through the semiconductor module 3 but is smaller than the outer shape of the heat receiving surface 30a of the heat sink 30 to be described later. Around the communication hole 12c, a seal groove 12d is provided on the back side that does not face the first case portion 11 . The seal groove 12d is a recess for accommodating the ring-shaped seal material 13 .

It can also be clearly seen from FIG. 2 that a partition wall portion 12e is provided on the second housing portion 12 to divide the back side of the second housing portion 12 into two left and right sides, and becomes the right half in FIG. 2 . The upper edge of the portion is provided with a ventilation plate portion 12f. The partition wall portion 12e is a flat plate-shaped member erected so as to be substantially perpendicular to the first case portion 11 . The ventilation plate portion 12f is a flat member having a plurality of ventilation holes 12g, and is provided so as to cover the upper part of the right half of the second case portion 12 in FIG. 2 .

The ventilation part 20 includes a frame member 40 configured to surround the second case part 12 , and a ventilation passage 21 along the vertical direction is formed between the second case part 12 and the frame member 40 . The upper end opening of the ventilation passage 21 is covered by the ventilation plate portion 12 f provided on the second case portion 12 . The frame member 40 is formed of a high thermal conductivity material having good thermal conductivity such as aluminum or an aluminum alloy, and has a main plate portion 41 , side plate portions 42 and auxiliary side plate portions 43 as shown in FIGS. 2 and 4 . The main plate portion 41 has an external dimension capable of covering a portion of the second case portion 12 located on the right side of the partition wall portion 12e. A plurality of fin fitting grooves 41 a are provided in the vertical direction on the inner surface of the main plate portion 41 facing the second case portion 12 . The side plate portion 42 is a portion extending from one edge of the main plate portion 41 toward the second case portion 12 in a direction substantially perpendicular to the main plate portion 41 . When the main plate portion 41 is opposed to the second case portion 12 , the side plate portion 42 is arranged to face the partition wall portion 12 e of the second case portion 12 . The auxiliary side plate portion 43 is a portion extending from the other edge of the main plate portion 41 toward the second case portion 12 in a direction substantially perpendicular to the main plate portion 41 . As can also be clearly seen from the drawings, the auxiliary side plate portion 43 is configured to be shorter than the length of the side plate portion 42 extending from the main plate portion 41 . The auxiliary side plate portion 43 is superimposed on the partition wall portion 12 e when the main plate portion 41 is opposed to the second case portion 12 .

On the inner surface of the frame member 40, a ventilation fan 50 and a radiator 30 are provided. As shown in FIG. 2 , the ventilation fan 50 is disposed on the lower end of the inner surface of the frame member 40 . When the ventilation fan 50 is driven, it operates by introducing external air into the ventilation passage 21 through the ventilation hole 12g of the ventilation plate portion 12f, and discharging the air in the ventilation passage 21 from the opening at the lower end. .

Like the frame member 40, the heat sink 30 is molded from a high thermal conductivity material having good thermal conductivity such as aluminum or an aluminum alloy. In this embodiment, the heat sink 30 which has the flat heat receiving surface 30a on one surface of a base member, and the many cooling fins 30b standingly provided on the other surface is used. The heat receiving surface 30 a of the heat sink 30 is formed in a rectangular shape of a size capable of abutting against the entire circumference of the sealing material 13 accommodated in the sealing groove 12 d of the second case portion 12 . The heat sink 30 is attached to the frame member 40 in a state thermally connected to the frame member 40 by fitting the front end portions of the cooling fins 30 b into the fin fitting grooves 41 a of the main plate portion 41 . The position where the heat sink 30 is installed with respect to the frame member 40 is such that the communication hole 12c of the second case part 12 is covered with the main plate part 41 facing the second case part 12, and the entire circumference of the sealing material 13 is The position facing the peripheral portion of the heat receiving surface 30a.

As shown in FIG. 7 , a pair of screw fixing holes 31 are set on the heat receiving surface 30 a of the radiator 30 . The screw fixing holes 31 are provided corresponding to the screw through holes 3 c of the screw fixing portion 3 a provided on the semiconductor module 3 . As shown in FIG. 3 , the mounting screws B are fixed in the screw fixing holes 31 of the heat sink 30 through the through holes 2 a of the main circuit board 2A, the through holes 2 a of the sub circuit board 2B and the screw through holes 3 c of the semiconductor module 3 . The mounting screw B has the function of bringing the heat dissipation surface 3b of the semiconductor module 3 into close contact with the heat receiving surface 30a of the heat sink 30 and also bringing the sealing material 13 of the second case portion 12 into close contact with the heat receiving surface 30a of the heat sink 30 .

The power conversion device 1 configured as described above is installed, for example, in a state where the ventilation unit 20 is exposed to the outside. The housing case 10 that accommodates the main circuit board 2A and the sub-circuit board 2B is separated from the ventilating portion 20 exposed to the outside by the second case portion 12 , so even if water such as rainwater enters the ventilating path 21 , and will not affect the control circuit and electronic components mounted on the main circuit board 2A and the sub circuit board 2B.

When the ventilation fan 50 is driven in the above-mentioned installation state, outside air is introduced into the inside of the ventilation passage 21 through the ventilation hole 12g of the ventilation plate portion 12f. The air introduced into the ventilation passage 21 is discharged to the outside of the ventilation passage 21 through the opening at the lower end after exchanging heat with the capacitor housing portion 12b and the heat sink 30 in this order. Therefore, the heat generated by the capacitor 4 and the semiconductor module 3 when the power conversion device 1 operates can be dissipated through the capacitor housing portion 12b and the heat sink 30 by using the air passing through the ventilation passage 21, thereby preventing damage to Electronic components on the main circuit board 2A and the sub circuit board 2B are affected by heat. Furthermore, in the power conversion device 1 described above, the capacitor housing portion 12 b is formed integrally with the main cover portion 12 a of the second case portion 12 . Therefore, regardless of the number of capacitors 4 mounted on circuit boards 2A, 2B, the number of components does not increase. In addition, there is no need to provide a sealing member for ensuring watertightness between the main cover portion 12a and the capacitor housing portion 12b. Therefore, it is possible to improve the cooling performance of the capacitor 4 without causing a problem of an increase in the number of parts and a problem of cumbersome assembly work.

In addition, in the above-mentioned embodiment, since the capacitor housing portion 12b is arranged in the ventilation passage 21 , the cooling performance of the capacitor 4 can be further improved.

In addition, in the said embodiment, each capacitor 4 was arrange|positioned in the independent capacitor accommodating part 12b, but this invention is not necessarily limited to this. For example, like Modification 1 shown in FIGS. 8 and 9 , the elliptical capacitor housing portion 112b and the second case portion 12 may be formed integrally, and a plurality of (two in the illustrated example) The capacitor 4 is accommodated in the capacitor housing portion 112b. In this case, it is desirable to configure the capacitor housing portion 112b such that the major axis of the ellipse is arranged along the ventilation direction (arrow A in FIG. 8 ) of the ventilation portion 20 . That is, in the case where the capacitor housing portion 112b is configured such that the major axis of the ellipse is disposed along the ventilation direction of the ventilation unit 20, the capacitor housing unit 112b does not hinder the ventilation of the ventilation unit 20, thereby improving the cooling performance of the capacitor 4 and the semiconductor module 3. The possibility of being affected disappears. In addition, in the modification 1 of FIG. 8 and FIG. 9, the same code|symbol as embodiment is attached|subjected to the structure similar to embodiment.

In addition, in the above-mentioned embodiment, the capacitor housing portion 12b is configured as a bottomed cylindrical airtight container. The opening (vent hole) 212c for ventilation is formed at the front end portion of 212b, and the heat released from the capacitor 4 into the capacitor housing portion 212b is directly released to the outside of the second case portion 12, thereby further improving the cooling performance. However, it is necessary to cover the ventilation opening 212c with the moisture-permeable waterproof sheet 212d so as to prevent entry of water such as rainwater and dust. In addition, in the modification 2 of FIG. 10 and FIG. 11, the same code|symbol as that of embodiment is attached|subjected to the structure similar to embodiment.

Claims (4)

1. a power inverter, is housed in case by the circuit substrate being provided with capacitor It is internal, it is characterised in that

Described case has main cap and capacitor resettlement section, described main cap and described circuit base The capacitor installed surface relative configuration of plate, described capacitor resettlement section is formed as on described main cap The form that the position corresponding with described capacitor is prominent to outside, thus in described capacitor is housed in Portion, described main cap is integrally formed with described capacitor resettlement section.

2. power inverter as claimed in claim 1, it is characterised in that

In the outside of described case, constitute in the position around described capacitor resettlement section and have ventilation Path, and it is configured with the draught fan that the side from described ventilation channel carries out ventilating towards the opposing party.

3. power inverter as claimed in claim 2, it is characterised in that

Described capacitor resettlement section is formed as oval column,

Multiple capacitors are housed in the inside of described capacitor resettlement section, multiple described capacitors with along The form in the ventilation direction of described ventilation channel is arranged on described circuit substrate.

4. power inverter as claimed in claim 1, it is characterised in that

The passage of ft connection with described case it is formed with in described capacitor resettlement section, and And utilize moisture-permeability waterproof sheet to cover described passage.