Heat dissipation device of inverter and photovoltaic inverter

Abstract

The heat dissipation device comprises a heat dissipation substrate, the heat dissipation device further comprises a limiting piece and a plurality of insulation heat conduction pieces, the heat dissipation substrate is provided with an installation plane, the limiting piece is arranged on the installation plane in a covering mode, the insulation heat conduction pieces are arranged on the installation plane in a covering mode, and the insulation heat conduction pieces are arranged on the installation plane in a covering mode. The limiting piece is made of an insulating material, a plurality of limiting through holes are formed in the limiting piece, one insulating heat-conducting piece is accommodated in each limiting through hole, and the insulating heat-conducting pieces are limited in the limiting through holes; each insulating heat-conducting fin is provided with a first surface which is in direct or indirect contact with a power device of the inverter, each insulating heat-conducting fin is also provided with a second surface which is opposite to the first surface, and the second surface is in contact with the heat dissipation substrate. The heat dissipation device provided by the utility model is relatively low in use cost.

Description

Technical Field

[0001] This utility model belongs to the field of power electronics technology, specifically relating to a heat dissipation device for inverters and a photovoltaic inverter. Background Technology

[0002] The IGBTs (Insulated Gate Bipolar Transistors) of the inverter need to be attached to a heatsink for insulation and heat dissipation. The heatsink needs to be attached to the surface of the heat sink for heat conduction. The traditional way to fix the heatsink in the industry is to first mill a groove on the heat sink (using a tool with a bottom cutting edge to cut a groove), and then put the ceramic substrate into the groove of the heat sink substrate. However, the milling cost on the heat sink is very high, especially when there are many heatsinks, the cost is even higher. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model provides a heat dissipation device for inverters, which has a low operating cost.

[0004] This utility model also provides a photovoltaic inverter, which is relatively easy to assemble.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A heat dissipation device for an inverter includes a heat sink, the heat sink including a heat dissipation substrate, the heat dissipation device further including a limiting plate and a plurality of insulating thermally conductive plates, the heat dissipation substrate having a mounting plane, the limiting plate covering the mounting plane, the limiting plate being made of an insulating material, the limiting plate having a plurality of limiting through holes formed thereon, each limiting through hole accommodating one of the insulating thermally conductive plates and the insulating thermally conductive plates being confined within the limiting through holes, each of the insulating thermally conductive plates having a first surface for direct or indirect contact with power devices of the inverter, each of the insulating thermally conductive plates also having a second surface opposite to the first surface, the second surface contacting the heat dissipation substrate.

[0007] In a preferred embodiment, the limiting piece is a one-piece molded plastic sheet. The plastic sheet has a low manufacturing cost, further reducing usage costs.

[0008] In a preferred embodiment, the thickness of the insulating thermally conductive sheet is greater than or equal to the thickness of the limiting sheet.

[0009] Specifically, the thickness of the insulating heat-conducting sheet is equal to the thickness of the limiting sheet.

[0010] In a preferred embodiment, the thickness of the insulating heat-conducting sheet is 1-3 mm, and the depth of the limiting through hole is 1-3 mm.

[0011] More specifically, the thickness of the insulating heat-conducting sheet is 1 mm; the depth of the limiting through hole is 1 mm.

[0012] In a preferred embodiment, the gap between the insulating heat-conducting sheet and the groove wall of the limiting through hole is 0.1-0.4 mm.

[0013] More specifically, the gap between the insulating heat-conducting sheet and the groove wall of the limiting through hole is 0.2 mm.

[0014] In a preferred embodiment, the melting point of the limiting piece is not lower than 110°C.

[0015] In a preferred embodiment, the limiting piece comprises a PC board.

[0016] In a preferred embodiment, the PC board is bonded to the heat dissipation substrate.

[0017] This utility model also adopts the following technical solution:

[0018] A photovoltaic inverter includes a housing and power devices disposed within the housing. The inverter also includes the aforementioned heat dissipation device, with the power devices disposed on the insulating heat-conducting sheet.

[0019] In a preferred embodiment, the inverter further includes a pressure block disposed between the insulating heat-conducting sheet and the circuit board of the inverter; the pressure block is provided with a snap-fit ​​element, which snaps onto the circuit board to pre-fix the power device.

[0020] In a preferred embodiment, the pressure block is provided with a mounting post integrally formed with the snap-fit ​​component, and the horizontal projection of the mounting post is located between the two insulating heat-conducting sheets; the inverter also includes a fastener that cooperates with the mounting post, the fastener passing through the circuit board, the mounting post and the heat dissipation substrate to press the pressure block against the insulating heat-conducting sheet.

[0021] The present invention adopts the above solution and has the following advantages compared with the prior art:

[0022] The heat dissipation device of this utility model has multiple limiting through holes on the insulating heat-conducting sheet. The insulating heat-conducting sheet is placed directly in the limiting through holes. The first surface of the insulating heat-conducting sheet is in contact with the power device, and the second surface is in contact with the heat dissipation substrate. While ensuring good heat conduction effect, it is easy to install and has low operating cost. Attached Figure Description

[0023] To more clearly illustrate the technical solution of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 An exploded view of the heat dissipation device according to an embodiment of the present utility model;

[0025] Figure 2 This is a top view of the heat dissipation device according to an embodiment of the present utility model;

[0026] Figure 3 This is a schematic diagram showing the power device disposed on the insulating heat-conducting sheet according to an embodiment of the present invention;

[0027] Figure 4 This is a partial schematic diagram of the inverter;

[0028] Figure 5 for Figure 4 A magnified view of a section at point A in the middle;

[0029] Figure 6 This is a partial 3D view of the inverter.

[0030] in,

[0031] 1. Heat dissipation device; 11. Radiator; 111. Heat dissipation base plate; 112. Heat dissipation fins; 113. Insulating thermal conductive sheet;

[0032] 2. Fixing plate; 21. Limiting through hole;

[0033] 3. Power devices; 31. Transistors; 32. Pins;

[0034] 4. Pressure block; 41. Clip-on component; 42. Mounting post; 5. Circuit board. Detailed Implementation

[0035] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art. It should be noted that the description of these embodiments is for the purpose of aiding understanding the present invention, but does not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] This embodiment provides an inverter, including a photovoltaic inverter. The photovoltaic inverter converts the variable DC voltage generated by photovoltaic solar panels into AC power at the mains frequency, which can be fed back to a commercial power transmission system or supplied to an off-grid grid. The photovoltaic inverter has a housing, power devices 3, and a heat dissipation device 1. The power devices 3 are located inside the housing. The main function of the heat dissipation device 1 is to quickly dissipate the heat generated by the power devices inside the inverter, maintaining the internal temperature of the inverter within a reasonable range. This ensures stable operation of the inverter in high-temperature environments, extends its service life, and improves its efficiency.

[0037] Reference Figures 1 to 6 As shown, the heat dissipation device 1 is specifically a heat sink 11. The heat sink 11 includes a heat dissipation substrate 111, an insulating heat-conducting sheet 113 and a heat dissipation fin 112 disposed on the heat dissipation substrate 111. The heat dissipation fin 112 is disposed on one side of the heat dissipation substrate 111, and the insulating heat-conducting sheet 113 is disposed on the other side of the heat dissipation substrate 111. The power device 3 is disposed on the insulating heat-conducting sheet 113. More specifically, the heat dissipation substrate 111 has a first end face facing the external environment and a second end face facing the inside of the housing. The heat dissipation fin 112 is disposed on the first end face, and the insulating heat-conducting sheet 113 is disposed on the second end face.

[0038] Furthermore, the heat dissipation fins 112 are straight and numerous, forming a heat dissipation channel between adjacent heat dissipation fins 112; the insulating heat-conducting sheets 113 are rectangular in shape and numerous, each corresponding to a power device. The insulating heat-conducting sheets can be distributed and arranged according to the heat source. In this embodiment, the power device is specifically an IGBT, a composite power semiconductor device that combines the high input impedance of a MOSFET with the low conduction loss of a BJT, and is widely used in power electronics.

[0039] The inverter also includes a pressure block 4, which is made of plastic and serves as insulation. The pressure block 4 is located between the insulating heat-conducting sheet 113 and the inverter's circuit board 5. Each pressure block 4 has two limiting through holes, and a power device is placed in each limiting through hole. Since each power device corresponds to one insulating heat-conducting sheet 113, one pressure block 4 can simultaneously press down two insulating heat-conducting sheets 113, resulting in high working efficiency.

[0040] Reference Figure 3As shown, the pressure block 4 is provided with a snap-fit ​​component 41 and a mounting post 42, which are integrally formed. The mounting post 42 is located in the middle of the pressure block 4. The snap-fit ​​component 41 is specifically a buckle, which is arranged around the mounting post 42. Specifically, there are two buckles arranged opposite each other. In other embodiments, the number of buckles is not limited to two. The circuit board 5 is provided with mounting holes for the mounting post 42 to be inserted. During assembly, the buckle passes through the mounting hole and snaps directly onto the circuit board 5 to pre-fix the power device 3. The horizontal projection of the mounting post 42 is located between the two insulating heat-conducting sheets 113. When fixing the pressure block 4, screws or other fasteners are usually used to tighten them by passing them through the mounting holes of the mounting post 42. As the screws are tightened, the power device on the pressure block 4 also comes into close contact with the insulating heat-conducting sheets 113, which can improve the heat dissipation effect of the power device.

[0041] During assembly, the pressure block 4 is first snapped onto the circuit board using the snap-fit ​​connector 41. Then, the power device 3 is held down and its pins are soldered. After soldering, the power device 3 and the circuit board 5 form a whole. This whole is placed directly on the insulating heat-conducting sheet 113. Finally, screws and other fasteners are used to pass through the circuit board 5, the mounting post 42, and the heat sink 11. As the screws are tightened, the power device 3 is pressed tightly onto the insulating heat-conducting sheet 113.

[0042] Unlike existing technologies that directly cut multiple grooves on the heat dissipation substrate 111 using tools, the heat dissipation device in this embodiment also includes a limiting piece 2. Multiple insulating heat-conducting sheets 113 are mounted on the heat dissipation substrate 111 via the limiting piece 2. Specifically, in this embodiment, the heat dissipation substrate 111 has a mounting plane, and the limiting piece 2 covers the mounting plane. The limiting piece 2 is made of insulating material and is fixed to the heat dissipation substrate 111 by adhesive bonding. It should be noted that this embodiment does not limit the method of mounting the limiting piece to the heat dissipation substrate; screws or other fixing methods can also be used. The limiting piece 2 is an integrally molded plastic sheet, specifically a PC board, also known as polycarbonate board, a high-performance engineering plastic sheet whose main component is polycarbonate, manufactured through co-extrusion technology. PC boards have characteristics such as high transparency, high temperature resistance, and impact resistance. In other embodiments, the limiting piece 2 can also use other materials, but the melting point must not be lower than 110°C to improve the safety of equipment operation.

[0043] Furthermore, referring to Figure 1As shown, the limiting plate 2 has multiple independently arranged limiting through holes 21. The limiting through holes 21 are mainly formed by die-cutting the limiting plate. The limiting through holes 21 are arranged sequentially in the longitudinal and transverse directions. Each limiting through hole 21 accommodates an insulating heat-conducting sheet 113, and the insulating heat-conducting sheet 113 is confined within the limiting through hole 21. Specifically, each limiting through hole 21 corresponds to one insulating heat-conducting sheet 113. The insulating heat-conducting sheet 113 has a first surface for direct contact with the power devices of the inverter and a second surface opposite to the first surface. The second surface contacts the heat dissipation substrate 111, further improving the heat conduction effect. In this embodiment, the insulating heat-conducting sheet 113 is specifically a thermally conductive ceramic pad. The thermally conductive ceramic pad is a material with high thermal conductivity, mainly composed of alumina. After being tightly combined with the power devices and heat sink, it can achieve ideal effects of dustproof, waterproof, thermally conductive, and insulating, and can adapt to harsh working environments with high temperature, high pressure, and high dust, improving the safety and stability of inverter operation.

[0044] The thickness of the insulating thermally conductive sheet 113 is greater than or equal to the thickness of the limiting sheet 2. Furthermore, the thickness of the thermally conductive ceramic pad is 1-3 mm, and the depth of the limiting through-hole 21 is 1-3 mm. Specifically, in this embodiment, the thickness of the thermally conductive ceramic pad is 1 mm, and the depth of the limiting through-hole 21 is 1 mm. The gap between the thermally conductive ceramic pad and the groove wall of the limiting through-hole 21 is 0.1-0.4 mm. Specifically, in this embodiment, the gap between the thermally conductive ceramic pad and the groove wall of the limiting through-hole 21 is 0.2 mm. This ensures a certain distance between the thermally conductive ceramic pad and the groove wall of the limiting through-hole 21, facilitating assembly while preventing the thermally conductive ceramic pad from falling out of the limiting through-hole 21. During assembly, the thermally conductive ceramic pad is directly placed into the limiting through-hole, making the operation relatively simple.

[0045] In this embodiment, there is no need to cut grooves on the heat dissipation substrate 111 of the heat sink 11. When assembling the insulating heat-conducting sheet 113 onto the heat sink, a 1mm thick PC board is first pasted onto the heat dissipation substrate 111 of the heat sink 11. Then, the thermally conductive ceramic pad is inserted into the limiting through hole 21 of the PC board to realize the installation of the ceramic substrate. The assembly is more convenient and the production cost is greatly reduced. Finally, the circuit board and power device are assembled and fixed onto the heat sink. The lower surface of the power device 3 is in close contact with the insulating heat-conducting sheet 113 to improve the heat dissipation effect.

[0046] As indicated in this specification and claims, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, and these steps and elements do not constitute an exclusive list; the method or apparatus may also include other steps or elements. The term "and / or" as used herein includes any combination of one or more of the associated listed items.

[0047] It should be noted that, unless otherwise specified, when a feature is referred to as "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or it can be indirectly fixed or connected to the other feature. Furthermore, the descriptions of "upper," "lower," "left," and "right" used in this utility model are only relative to the relative positional relationships of the various components of this utility model in the accompanying drawings.

[0048] The above embodiments are only for illustrating the technical concept and features of this utility model, and are preferred embodiments. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it accordingly, and should not be construed as limiting the protection scope of this utility model. All equivalent transformations or modifications made based on the principles of this utility model should be covered within the protection scope of this utility model.

Claims

1. A heat dissipating device of an inverter comprising a heat sink, the heat sink comprising a heat dissipation substrate, characterized by, The heat dissipation device further includes a limiting plate and a plurality of insulating heat-conducting plates. The heat dissipation substrate has a mounting plane, the limiting plate is covered on the mounting plane, the limiting plate is made of insulating material, and a plurality of limiting through holes are formed on the limiting plate. Each limiting through hole accommodates an insulating heat-conducting plate and the insulating heat-conducting plate is confined in the limiting through hole. Each insulating heat-conducting plate has a first surface for direct or indirect contact with the power devices of the inverter, and each insulating heat-conducting plate also has a second surface opposite to the first surface, the second surface being in contact with the heat dissipation substrate.

2. The heat dissipating device according to claim 1, wherein The limiting piece is a one-piece molded plastic sheet.

3. The heat dissipating device of claim 2, wherein, The plurality of limiting through holes are formed by die-cutting on the limiting piece.

4. The heat dissipating device according to claim 3, wherein The thickness of the insulating heat-conducting sheet is greater than or equal to the thickness of the limiting sheet.

5. The heat dissipating device of claim 1, wherein The thickness of the insulating heat-conducting sheet is 1-3mm, and the depth of the limiting through hole is 1-3mm.

6. The heat dissipating device according to claim 5, wherein The gap between the insulating heat-conducting sheet and the groove wall of the limiting through hole is 0.1-0.4 mm.

7. The heat dissipating device of claim 2, wherein The melting point of the limiting piece is not lower than 110°C; the limiting piece includes a PC board, which is bonded to the heat dissipation substrate.

8. A photovoltaic inverter, comprising a housing and power devices disposed within the housing, characterized in that, The inverter includes a heat dissipation device as described in any one of claims 1 to 7, wherein the power device is disposed on the insulating heat-conducting sheet.

9. The photovoltaic inverter of claim 8, wherein, The inverter also includes a pressure block disposed between the insulating heat-conducting sheet and the inverter's circuit board; the pressure block is provided with a snap-fit ​​component, which snaps onto the circuit board to pre-fix the power device.

10. The photovoltaic inverter of claim 9, wherein, The pressure block is provided with a mounting post integrally formed with the snap-fit ​​component. The horizontal projection of the mounting post is located between the two insulating heat-conducting sheets. The inverter also includes a fastener that cooperates with the mounting post. The fastener passes through the circuit board, the mounting post, and the heat dissipation substrate to press the pressure block against the insulating heat-conducting sheet.

Images