KR20170055605A - invertor for direct cooling of capacitor - Google Patents

Abstract

The present invention relates to a capacitor direct cooling inverter for providing a compact structure cooling means. The inverter comprises: a DC capacitor which has a ring-type cover unit for maintaining airtightness of cooling water, and an outer case coupled to the ring-type cover unit by insert injection and having an opened upper part; a terminal block unit which is disposed in the upper portion of the DC capacitor to be supported from an upper part of the ring-type cover unit; a heat exchange housing which is coupled to the bottom of the ring-type cover unit, and includes a chamber vertically penetrated by the outer case; a lower cover unit which surrounds the lower portion of the DC capacitor and the lower portion of the heat exchange housing; a plurality of power modules which are installed outside the heat exchange housing and come in surface contact with the same; and a printed circuit board unit which is disposed on the bottom of the lower cover unit, and is connected to the power modules. The power modules and the DC capacitor are cooled by heat exchange with cooling water flowing between the chamber and the cooling device.

Description

[0001] The present invention relates to an invertor for direct cooling of a capacitor,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an inverter of a direct cooling type capacitor, and more particularly to an inverter of a direct cooling type capacitor cooling a power module and a DC (direct current) capacitor of an inverter .

2. Description of the Related Art In recent years, various technologies have been applied to an inverter for an electric motor vehicle or an automobile to realize miniaturization and weight reduction.

Particularly, in the development of an inverter, it is required to realize a heat dissipation structure of various internal parts and to secure durability of the inverter.

DC capacitors, which directly affect the durability of the inverter, are temperature and durability. Therefore, the temperature of the DC capacitor is controlled by using the air-cooled or water-cooled cooling system. do.

In the inverter to which the DC capacitor indirect cooling method according to the related art is applied, a DC capacitor is mounted in the inverter casing, and a cooling device is provided on the opposite side of the casing in which the DC capacitor is mounted.

The cooling system is a natural air cooling system or a cooling water circulation system. The cooling system corresponds to the indirect cooling method because the natural air cooling system or the cooling water circulation system is also transmitted through the heat casing.

In the prior art, the capacitor has a structure in which the capacitor is in close contact with the casing for cooling the DC capacitor. However, this has the disadvantage that the casing size of the inverter as a whole increases. For example, since the power module and the DC capacitors are stacked and mounted in the casing in a stacked package manner, in order to simultaneously cool the power module and the DC capacitor, the cooling flow path of the casing needs to have an area exceeding the cross sectional area of the power module and the DC capacitor So that the casing size is increased.

In addition, the cover of the DC capacitor is made of a plastic resin material for electrical insulation, and the material has a high thermal resistance, which deteriorates the thermal conductivity and thus deteriorates the cooling effect.

The lower the cooling effect, the lower the durability of the DC capacitor and the factor that reduces the life span of the inverter.

Further, in the case of the indirect cooling method, since the allowable range temperature margin at the time of energization is smaller than that of the direct cooling method, the temperature margin must be designed to be high, and the total size of the inverter is also increased.

The object of the present invention has been achieved in view of the above-described circumstances, and it is an object of the present invention to provide a liquid crystal display device which can be configured to have a relatively small volume as compared with a stacked package type while adopting a structure for cooling power modules and DC capacitors simultaneously, It is possible to provide a direct cooling type inverter for the capacitor.

According to another aspect of the present invention, there is provided an inverter of a direct cooling type according to the present invention, comprising: a ring-shaped cover part for maintaining the airtightness of cooling water; a DC Direct Current) Capacitors; A terminal block portion disposed on the DC capacitor to be supported on the ring-shaped cover portion; A heat exchange housing coupled to a bottom surface of the ring-shaped cover portion and having a chamber through which the outer case vertically penetrates; A lower cover portion surrounding the bottom portion of the DC capacitor and the bottom portion of the heat exchange housing; A plurality of power modules provided on the outer side of the heat exchange housing and in surface contact with each other; And a printed circuit board portion disposed on a bottom surface of the lower cover portion and connected to the power module. The power module and the DC capacitor are cooled by heat exchange through cooling water flowing between the chamber and the cooling device.

The DC capacitor includes a stepped lower portion formed at four corner positions of the ring-shaped cover portion and a stepped upper portion having an upper surface protruding higher than the bottom surface of the lower portion of the stepped portion between the lower portion of the stepped portion, A power module fastening terminal extending from the capacitor element and protruding and bent from the epoxy mold to be disposed below the step or above the step, and a power module fastening terminal extending from the power module fastening terminal, And a pair of input terminals extending from the capacitor element and protruding and bent from the epoxy mold so as to be disposed above the stepped portion so as not to overlap with each other.

The outer case and the heat exchange housing are made of a metal material or an aluminum alloy material.

Wherein the terminal block portion includes a block body disposed on the epoxy mold, and four side surfaces of the block body integrally protruding from the four sides of the block body, A leg supported on the upper surface of the stepped portion, and an upper contact plate spaced apart from the upper surface of the block body.

The upper contact plate includes a three-phase bus bar connected to the motor, and a single-phase bus connected to the battery.

The Y-cap is connected to the three-phase bus bar or the single-phase bus bar. The Y-cap is disposed on the bottom surface of the terminal block to reduce noise. The Y- And a plurality of bus bar ends protruding and bent from the side bottom surface and extending horizontally, wherein the bus bar end faces the input terminal of the DC capacitor or the module terminal of the power module.

Wherein the heat exchange housing includes three groove portions formed between the corner portions of the heat exchange housing, a cooling fin protruding from a plurality of inner surfaces of the groove portion, and a cooling water outlet formed on the side wall portion of the heat exchange housing without the cooling fin .

The inverter of the direct cooling type according to the present invention has a structure in which a DC capacitor is inserted into a heat exchange housing having a rectangular ring-shaped cross section and a power module is connected to the outside of the heat exchange housing, Size can be minimized, so that it is possible to realize a miniaturized inverter.

The inverter of the direct cooling type of the capacitor according to the present invention is configured such that the bottom and sides of the DC capacitor are made of a metallic material or an external case made of an aluminum alloy material so that the cold heat of the heat exchange housing can be efficiently transferred to the DC capacitor, The heat resistance is relatively low and the thermal conductivity is relatively higher than that of the material, so that the cooling performance can be improved.

The capacitor direct cooling type inverter according to the present invention realizes a direct cooling method in which the cooling water inside the heat exchange housing directly contacts the bottom surface and the side surface of the DC capacitor constituted by the external case, The DC capacitor can be reduced in size compared to the conventional indirect cooling method and the inverter output density can be improved and the DC capacitor or the power module as the heating element of the inverter can be reduced, The lifespan of the device can be increased.

1 is a perspective view of an inverter of a direct cooling type capacitor according to an embodiment of the present invention;
FIG. 2 is an exploded perspective view of the inverter of the direct cooling type of the capacitor shown in FIG. 1; FIG.
Figure 3 is a perspective view of the DC capacitor shown in Figure 2;
FIG. 4 is a perspective view showing a combined DC capacitor and a heat exchange housing shown in FIG. 2; FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. And is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined by the claims.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. &Quot; comprises " and / or "comprising" when used in this specification is taken to specify the presence or absence of one or more other components, steps, operations and / Or add-ons. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of an inverter of a direct cooling method according to an embodiment of the present invention.

Referring to FIG. 1, the present embodiment includes a direct current (DC) capacitor 100, a terminal block unit 200, a heat exchange housing 300, a lower cover unit 400, a power module 500, The power module 500 and the DC capacitor 100 are configured to be cooled by heat exchange through the cooling water flowing between the chamber of the heat exchange housing 300 and the cooling device (not shown)

DC capacitor 100 can perform direct cooling type heat exchange with cooling water, and sufficient temperature control is performed at this time, thereby solving the problem that capacitor capacity is increased in terms of temperature management. By reducing capacitor capacity relatively , It is possible to reduce the weight of the entire inverter.

2 is an exploded perspective view of the inverter of the direct cooling type of the capacitor shown in FIG.

Referring to FIG. 2, the DC capacitor 100 includes a ring-shaped cover portion 110 for maintaining the air-tightness of the cooling water, and an outer case 120 coupled to the ring-shaped cover portion 110 by insert injection, .

The outer case 120 may be made of a metal material or an aluminum alloy, or may be made of a material having a relatively high thermal conductivity as compared with a plastic material.

The ring-shaped cover portion 110 is made of a releasing material as compared with the case 120. For example, the ring-shaped cover portion 110 may be made of an engineering plastic material that does not melt at a melting point of 300 캜 and has excellent flame retardancy and high heat resistance, such as polyphenylene sulfide (PPS).

The ring-shaped cover part 110 is joined (for example, fused) to the upper part of the heat exchange housing 300 to serve as a cover for closing the upper opening part of the heat exchange housing, As shown in FIG.

The terminal block portion 200 is disposed on the DC capacitor 100 so as to be supported on the ring-shaped cover portion 110.

The heat exchange housing 300 has a rectangular ring-shaped cross section. The heat exchange housing 300 is coupled to the bottom surface of the ring-shaped cover portion 110 and has a chamber 310 through which the case 120 is vertically inserted or penetrated.

The chamber 310 is opened at an upper portion and a lower portion of the chamber 310 with respect to a vertical direction so as to pass through the outer case 120 of the DC capacitor 100.

The heat exchange housing 300 forms a cooling flow passage through which the cooling water flows when the casing 120 of the DC capacitor 100 is fitted in the chamber 310 located inside the rectangular ring-shaped cross section.

That is, since the cooling flow path through which the cooling water flows is formed along the circumference of the case 120 of the DC capacitor 100, the size of the cooling flow path can be minimized, and the miniaturized inverter can be realized.

Such a chamber 310 has a volume such that cooling water can be filled between the outer case 120 and the inner surface of the chamber 310.

The outer wall of the chamber 310 is surrounded by the heat exchange housing 300 and the ceiling of the chamber 310 is closed by the ring cover 110 of the DC capacitor 100, The bottom is closed by the lower cover part 400.

The cooling water supplied to the chamber 310 directly contacts the outer case 120 of the DC capacitor 100 to perform direct cooling type heat exchange.

The heat exchange housing 300 may be made of a metal material or an aluminum alloy or may be made of a material having relatively higher thermal conductivity than the plastic material or the same material as the material of the case 120.

The heat exchange housing 300 can be roughly produced by an extrusion profile manufacturing method.

The lower cover part 400 functions to cover the bottom part of the DC capacitor 100 (for example, the lower end part of the case 120) and the bottom part of the heat exchange housing 300.

The upper rim of the lower cover part 400 may be welded or bonded to the bottom surface of the heat exchange housing 300.

A plurality of flow passages (not shown) for introducing or discharging cooling water are formed on the outside and inside of the lower cover part 400 to supply or recover the cooling water to the cooling water inlet or the cooling water outlet of the heat exchange housing 300 Can also play a role.

The power module 500 may be composed of a plurality of (e.g., three) power modules.

Each of the power modules 500 may be an IGBT (Insulated Gate Bipolar Transistor) of a transfer mold type.

The power module 500 is installed on the outer side of the heat exchange housing 300 and is in surface contact with three sides of the heat exchange housing 300.

The power module 500 includes a module main body 510 having a power conversion switching device for converting a direct current into an alternating current and a power module 500 that protrudes from the upper portion of the module main body 510 and extends toward the DC capacitor 100 or the terminal block portion 200 And a plurality of folded module terminals 520 and a plurality of lead wires 530 protruding from the bottom of the module main body 510 and extending toward the printed circuit board portion 600. The ends of the respective lead wires 530 may be connected to the printed circuit board portion 600 by soldering.

The power module 500 is formed with a pair of bolt holes 540 which are penetrated in the thickness direction of the module body 510 and spaced apart from each other in the longitudinal direction. Mounting bolts are coupled to the bolt holes 540, and the mounting bolts are respectively coupled to mounting holes 301 formed on three side surfaces of the heat exchange housing 300. As a result, the surface of the module body 510 of the power module 500 is directly in surface contact with the outer surface of the heat exchange housing 300, and heat exchange can be performed.

A thermal conductive pad or a thermal grease layer 550 may be interposed between the surface of the module body 510 of the power module 500 and the outer surface of the heat exchange housing 300 to increase the thermal conductivity by eliminating voids.

The printed circuit board unit 600 is disposed on the bottom surface of the lower cover unit 400 and is connected to the power module 500 and processes internal signals.

(Not shown) is further formed on the upper surface of the rim of the printed circuit board portion 600 and a fixing hole (not shown) is further formed on the bottom surface of the lower cover portion 400 with reference to a position coinciding with the mounting hole do. The printed circuit board portion 600 may be fixed to the bottom surface of the lower cover portion 400 using an attachment hole, a fixing hole, and a mounting bolt (not shown).

3 is a perspective view of the DC capacitor shown in FIG.

3, the DC capacitor 100 includes a stepped lower portion 111 formed at four corner positions of the ring-shaped cover portion 110 and a stepped bottom portion 111 formed between the stepped lower portion 111 and the bottom of the stepped lower portion 111, And a step upper portion 112 having an upper surface that is higher than the surface.

The ring-shaped cover portion 110 and the outer case 120 are combined with each other through insert injection, and the lower step portion 111 and the upper step portion 112 are formed.

The DC capacitor 100 includes an epoxy mold 130 filled in the outer case 120 to protect the capacitor element (not shown) inside the outer case 120.

DC capacitor 100 includes power module fastening terminals 140 that extend from the capacitor element and protrude and bend from the epoxy mold 130 to be disposed in the step lower portion 111 or the step upper portion 112.

The power module coupling terminals 140 have the same polarity or different polarities and can be connected to the corresponding module terminals 520 of the power module 500 shown in FIG. 2 with the same polarity.

DC capacitor 100 is connected to a pair of input terminals 150 (not shown) extending from the capacitor element so as not to overlap power module clamping terminal 140 and being protruded and bent at epoxy mold 130, ).

The power module fastening terminal 140 and the input terminal 150 are formed with coupling holes 141 and 151 penetrating in the terminal thickness direction so as to be used for soldering.

1, the terminal block unit 200 includes a block body 210 disposed on the epoxy mold 130 and four side surfaces of the block body 210 integrally protruding from the input terminal 150 or a leg 220 supported on an upper surface of the step upper portion 112 corresponding to a position not overlapping with the power module fastening terminal 140.

The bottom surface of the leg 220 is bonded to the upper surface of the stepped upper portion 112 of the DC capacitor 100 by adhesive or fusion.

The terminal block unit 200 includes an upper contact plate 230 spaced from the upper surface of the block body 210.

The upper contact plate 230 includes a three-phase bus bar 232 connected to or in contact with a motor (not shown), and a single-phase bus bar 231 connected to or in contact with the battery (not shown).

The terminal block unit 200 is electrically connected to the single-phase bus bar 231 so as to reduce noises. The terminal block unit 200 is connected to the bottom of the terminal block unit 200, Cap 240 (Y-cap).

The Y cap 240 is interposed between the terminal block portion 200 and the DC capacitor 100.

The terminal block unit 200 is connected to the three-phase bus bar 232 or the single-phase bus bar 231. The terminal block unit 200 includes a plurality of horizontally extended bus bar ends protruding from the bottom- (250, 251). One end of the bus bar 250 is connected to the input terminal 150 of the DC capacitor 100 and the other end of the bus bar 251 is connected to the module terminal 520 of the power module 500 And the surface-contacting portions here can be joined to each other through soldering so as to be in an electrically energized state.

FIG. 4 is a perspective view showing the combined DC capacitor and the heat exchange housing shown in FIG. 2. FIG.

4, the heat exchange housing 300 includes three grooves 330 formed between the corners 320 of the heat exchange housing 300 and a plurality of grooves 330 protruding from the inner surface of the grooves 330 And a pin 331.

That is, the chamber 310 of the heat exchange housing 300 can have a relatively large heat exchange area compared to a structure having a simple inner surface due to the shape or structure of the groove portion 330 and the cooling fin 331.

The space around the groove portion 330 and the cooling fin 331 may be a cooling passage through which the cooling water W flows.

The cooling water W that can circulate (e.g., supply and recover) is filled in the chamber 310 and the cooling water W can directly contact the outer case 120 of the DC capacitor 100. [ More specifically, the cooling water W in the chamber 310 can directly contact the surfaces (for example, four side surfaces and bottom surface) of the exterior case 120 except for the epoxy mold to perform heat transfer or heat exchange have.

A cooling water outlet 341 and a discharge passage are formed in the side wall portion 340 of the heat exchange housing 300 without the cooling fin 331. The cooling water outlet 341 is connected to the oil passage 410 for discharging the cooling water of the lower cover part 400 mentioned above.

The end of the discharge passage opposite to the cooling water outlet 341 is connected to the inner space of the chamber 310.

The cooling water W may be introduced into the chamber 310 through the passage 420 for introducing the cooling water of the lower cover part 400 and through the place where each cooling fin 331 is located.

In connection with the cooling water outlet 341, an inlet 342 of the discharge passage formed to penetrate the chamber 310 is formed on the inner surface of the side wall portion 340.

Therefore, the introduced cooling water W performs heat exchange with the DC capacitor 100 or the power module, and then the cooling water outflow of the inlet 342, the cooling water outlet 341 and the lower cover part 400 of the discharge passage To the cooling device (not shown) via the flow path 410 for the cooling water.

In order to avoid interference with a piping line (not shown) connected to the cooling water outlet 341, to secure an access path for the piping line, or to secure a space for entry of the socket connection cable, A slot 610 in the form of a slot is further provided on the side of the unit 600.

The foregoing description is merely illustrative of the technical idea of the present invention and various changes and modifications may be made without departing from the essential characteristics of the present invention. Therefore, the embodiments described in the present invention are not intended to limit the scope of the present invention, but are intended to be illustrative, and the scope of the present invention is not limited by these embodiments. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents, which fall within the scope of the present invention as claimed.

100: DC capacitor 200: Terminal block part
300: heat exchange housing 400: lower cover part
500: power module 600: printed circuit board part

Claims (7)

A direct current (DC) capacitor having an annular cover portion for maintaining the airtightness of the cooling water, an outer case coupled to the annular cover portion by insert injection and having an open upper portion;
A terminal block portion disposed on the DC capacitor to be supported on the ring-shaped cover portion;
A heat exchange housing coupled to a bottom surface of the ring-shaped cover portion and having a chamber through which the outer case vertically penetrates;
A lower cover portion surrounding the bottom portion of the DC capacitor and the bottom portion of the heat exchange housing;
A plurality of power modules provided on the outer side of the heat exchange housing and in surface contact with each other;
And a printed circuit board portion disposed on a bottom surface of the lower cover portion and connected to the power module,
Wherein the power module and the DC capacitor are cooled by heat exchange through cooling water flowing between the chamber and the cooling device
In capacitor Direct cooling type inverter.
The method according to claim 1,
The DC capacitor includes:
A stepped lower portion formed at four corner positions of the ring-shaped cover portion,
A stepped upper portion having an upper surface protruding higher than a bottom surface of the lower portion of the step between lower portions of the stepped portions,
An epoxy mold filled in the case to protect a capacitor element inside the case,
A power module fastening terminal extending from the capacitor element and protruding and bent from the epoxy mold to be disposed below the step or over the step,
And a pair of input terminals extending from the capacitor element so as not to overlap with the power module clamping terminal and being protruded and bent from the epoxy mold and disposed on the top of the step
In capacitor Direct cooling type inverter.
3. The method of claim 2,
Wherein the outer case and the heat exchange housing are made of a metal material or an aluminum alloy material
In capacitor Direct cooling type inverter.
3. The method of claim 2,
The terminal block unit includes:
A block body disposed above the epoxy mold,
A leg supported on an upper surface of the upper portion of the step corresponding to a position between the input terminals or a position not overlapping the power module fastening terminals,
And an upper contact plate spaced apart from the upper surface of the block body
In capacitor Direct cooling type inverter.
5. The method of claim 4,
The upper contact plate includes a three-phase bus bar connected to the motor, and a single-phase bus connected to the battery
In capacitor Direct cooling type inverter.
6. The method of claim 5,
The terminal block unit includes:
A Y cap (Y-cap) arranged on the bottom surface of the terminal block portion to reduce noise by being energized by the single-phase bus bar, and
And a plurality of horizontally extending bus bar ends connected to the three-phase bus bar or the single-phase bus bar and protruding and bent from a bottom-side bottom surface of the block body,
Wherein the end of the bus bar is in surface contact with an input terminal of the DC capacitor or a module terminal of the power module
In capacitor Direct cooling type inverter.
The method according to claim 1,
Wherein the heat exchange housing comprises:
Three groove portions formed between the corner portions of the heat exchange housing,
A plurality of cooling fins projecting from the inner surface of the groove portion, and
And a cooling water outlet formed in the side wall of the heat exchange housing without the cooling fin
In capacitor Direct cooling type inverter.

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